HowTo: Logging Wideband AFR via Rear O2 ECU ADC Input (Logging AFR without serial)
Newbie
Joined: Jun 2007
Posts: 30
Likes: 3
From: Singapore
LC-1 sensor mounted on test pipe
exos = JIC
Reading 2bytes on Aussie RomID 53040010 RequestID=23809346
Eval = x * 0.0146+7.35
Spot on compared to Guage reading on LC-1
Using JDM RomID 52360018 and Eval = x, Request =23808665
results:
AFR 7.6=0 (cold heater)
AFR 22.4=58880 (free air)
Eval = x / 3978 +7.6 (no good, reading too far out)
Eval = x / 3950 + 8.03
Almost there but not close enough
Will compare it using another LC-1 at the tail pipe and fine tune the EVAL over the weekend.
exos = JIC
Reading 2bytes on Aussie RomID 53040010 RequestID=23809346
Eval = x * 0.0146+7.35
Spot on compared to Guage reading on LC-1
Using JDM RomID 52360018 and Eval = x, Request =23808665
results:
AFR 7.6=0 (cold heater)
AFR 22.4=58880 (free air)
Eval = x / 3978 +7.6 (no good, reading too far out)
Eval = x / 3950 + 8.03
Almost there but not close enough
Will compare it using another LC-1 at the tail pipe and fine tune the EVAL over the weekend.
Newbie
Joined: Jun 2008
Posts: 49
Likes: 0
From: NC
O2 Sensor Front or Back
HOW TO:
Logging Wideband AFR via Rear O2 ECU ADC Input (Logging AFR without serial)
Parts Needed:
- Wideband O2 (I used an AEM UEGO)
Tools Required:
- OpenPort 2.0 Cable
- ECUFlash
- EvoScan
(I imagine Cobb AP and ATR could do this as well, but I won't go into details)
- Laptop
- Flashlight
- Electrical Tape
- Knife
- Wire Taps
- Soldering Iron/Solder
- Philips Screwdriver
- 10mm & 14mm Sockets
- Ratchet
Recommended Number of People
- Hopefully 1, though an extra set of hands is nice!
Difficulty
- 3 out of 10 if you've already got ECUFlash installed
Time to complete
- Give yourself a bit of time, especially if you've never removed the seat or dash trim. Call it one hour with experience with the dash trim.
Step by Step Instructions
0 - First off, you need to remove the rear O2 sensor from the exhaust stream. When you disable the O2 sensor, you disable its heater and as a result the sensor will be damaged if exposed to exhaust temperatures. I will not go into details on how to do this, because you should have it done already before starting this tutorial. You can either remove the O2 sensor from the car completely or just wrap it and tie it up (as I did) out of the way.
Then, it helps to have a bit of understanding as to what we are trying to accomplish. Basically, as the below diagram shows, the ECU receives an analog signal from the O2 sensor, which is then converted into a digital signal for the ECU to use. What we want to do is replace the O2 sensor signal with a WB sensor signal so that we can log it in EvoScan. If you look at the diagram, all we are really doing is replacing the yellow wire's input, so that it is sending your WB signal instead.
Part I
1 - Here is where we are working. The Rear O2 sensor wiring runs through a grommet under the passenger seat and is (sort of) accessible through a flap in the carpet. If you have small hands, it is a little easier. Make sure you move the seat all the way back!
2 - Unplug the O2 sensor harness and tape the O2 sensor side nicely out of the way, so it doesn't rattle around.
3 - Unclip the other connector from it's nice little holding spot (it probably already came off while you were unplugging the connectors) so you can actually work with it.
4 - You should be able to see the yellow wire that we are going through all this trouble to get to. At this point, you'll probably decide that this was an easy project! Then you'll realize that there is no way that you can get that wire tapped in that tiny *** amount of space.
5 - I ended up unbolting [14mm] the passenger seat (no need to unclip harnesses, we aren't going far) and sliding it back as far as possible to give a bit more working room.
6 - Once the seat is move back a bit, you'll realize that there still isn't any room, as the heater duct is what is actually causing you problems. Fortunately, with the seat out of the way, a small (unnoticeable) incision into the carpet can pull the wires and harness up into a workable amount of space. Just cut an area so that you can reach in and find the connector, then pull it through.
7 - Tap into the yellow wire. I used taps, some will solder. It isn't a high current wire, the tap should be fine. Then, push the connector back down and clip it back into it's holding clip.
8 - What are we tapping/vamping into? Well, the 0-5V Analog output of you Wideband O2 Sensor. I have an AEM UEGO, which has a white wire (pictured) coming off the back of the gauge. This is the wire I need to get to the yellow wire. Depending on where your gauge is located, your routing method will be different.
9 - In my case, I used red wire to extend the yellow wire connection up the side of the passenger area, up the corner and behind the glovebox. Also, I added a quick disconnect so that I could go back to stock if necessary without tearing everything apart again. I already have a ton of wires routed this way from my stereo install, so it wasn't like it was new to me. For those who haven't done this, don't be scared. Pinch the glovebox in, unclip the hydraulic thing from the glovebox and pull the glovebox out. There are 4 screws and a clip that need to be removed, but then you can route any wire you want! (The green/black wires are my serial cable, which stopped working leading to this project)
10 - Behind the stereo area (which is where I have my gauges, you might have a different setup), the red wire was soldered to the white analog wire, and while I was there I relocated the UEGO ground. Ever since I installed it, there was a high pitched whine that irritated the hell out of me but I couldn't be bothered to open this up again. It was originally grounded to the stereo ground, I simply relocated it to a bolt [10mm] (visible in the picture).
11 - Reinstalled the gauges and trim, and done!
Part II
Now that we have an input into the ECU, we need to actually record from it! Our outline is: disable rear O2 sensor, setup EvoScan to record input, log away!
1 - Disabling the rear O2 sensor is done by toggling bit.1 of ECU Options #2. Simply open up your ROM in ECUFlash, find the table "ECU Options #2" and use the "[" key to toggle bit.1 . This updated ROM needs to be flashed to the car. This "Disable" of the O2 sensor DOES NOT necessarily mean you won't get CELs. What we really need is an O2 simulator patch, which is not yet available for the X. I have a CEL, but it doesn't really matter, the future will get rid of that for us.
2 - EvoScan time! First, we need to do some math. Find the documentation for you gauge/wideband, we need to determine the formula that relates the analog voltage to what the AFR is. Look at the documentation, if it lists a transfer function, that's what we want. If not, find the formula yourself by looking at the 0V and 5V AFR and working it out.
For the new AEM Analog WB Gauge, AFR = 2.375*V + 7.3125
For my AEM UEGO Gauge, AFR = 2*V + 10.
This is almost the formula EvoScan needs. We can't input "V" into EvoScan, we need it to be an ECU parameter. Fortunately, we just tapped into the ADC! Therefore,
V = 5*ADC/1023
In my 52680020 ROM, the ADC Memory Address is a 2byte value at 0x80934E.
After testing out the new logging parameter, I had to adjust the formula a bit to get it to actually match the proper gauge output. My output was reading too high, so I had to offset the calculation slightly. My final formula and information is shown in the pictures.
Therefore, what we actually put in EvoScan looks like this. To get this screen, select the 2008 Mode23 USDM EvoX from the dropdown box, right click where the logging items are and edit. Click Add New at the bottom, and enter the details.
3 - Finally, logging time!
Logging Wideband AFR via Rear O2 ECU ADC Input (Logging AFR without serial)
Parts Needed:
- Wideband O2 (I used an AEM UEGO)
Tools Required:
- OpenPort 2.0 Cable
- ECUFlash
- EvoScan
(I imagine Cobb AP and ATR could do this as well, but I won't go into details)
- Laptop
- Flashlight
- Electrical Tape
- Knife
- Wire Taps
- Soldering Iron/Solder
- Philips Screwdriver
- 10mm & 14mm Sockets
- Ratchet
Recommended Number of People
- Hopefully 1, though an extra set of hands is nice!
Difficulty
- 3 out of 10 if you've already got ECUFlash installed
Time to complete
- Give yourself a bit of time, especially if you've never removed the seat or dash trim. Call it one hour with experience with the dash trim.
Step by Step Instructions
0 - First off, you need to remove the rear O2 sensor from the exhaust stream. When you disable the O2 sensor, you disable its heater and as a result the sensor will be damaged if exposed to exhaust temperatures. I will not go into details on how to do this, because you should have it done already before starting this tutorial. You can either remove the O2 sensor from the car completely or just wrap it and tie it up (as I did) out of the way.
Then, it helps to have a bit of understanding as to what we are trying to accomplish. Basically, as the below diagram shows, the ECU receives an analog signal from the O2 sensor, which is then converted into a digital signal for the ECU to use. What we want to do is replace the O2 sensor signal with a WB sensor signal so that we can log it in EvoScan. If you look at the diagram, all we are really doing is replacing the yellow wire's input, so that it is sending your WB signal instead.
Part I
1 - Here is where we are working. The Rear O2 sensor wiring runs through a grommet under the passenger seat and is (sort of) accessible through a flap in the carpet. If you have small hands, it is a little easier. Make sure you move the seat all the way back!
2 - Unplug the O2 sensor harness and tape the O2 sensor side nicely out of the way, so it doesn't rattle around.
3 - Unclip the other connector from it's nice little holding spot (it probably already came off while you were unplugging the connectors) so you can actually work with it.
4 - You should be able to see the yellow wire that we are going through all this trouble to get to. At this point, you'll probably decide that this was an easy project! Then you'll realize that there is no way that you can get that wire tapped in that tiny *** amount of space.
5 - I ended up unbolting [14mm] the passenger seat (no need to unclip harnesses, we aren't going far) and sliding it back as far as possible to give a bit more working room.
6 - Once the seat is move back a bit, you'll realize that there still isn't any room, as the heater duct is what is actually causing you problems. Fortunately, with the seat out of the way, a small (unnoticeable) incision into the carpet can pull the wires and harness up into a workable amount of space. Just cut an area so that you can reach in and find the connector, then pull it through.
7 - Tap into the yellow wire. I used taps, some will solder. It isn't a high current wire, the tap should be fine. Then, push the connector back down and clip it back into it's holding clip.
8 - What are we tapping/vamping into? Well, the 0-5V Analog output of you Wideband O2 Sensor. I have an AEM UEGO, which has a white wire (pictured) coming off the back of the gauge. This is the wire I need to get to the yellow wire. Depending on where your gauge is located, your routing method will be different.
9 - In my case, I used red wire to extend the yellow wire connection up the side of the passenger area, up the corner and behind the glovebox. Also, I added a quick disconnect so that I could go back to stock if necessary without tearing everything apart again. I already have a ton of wires routed this way from my stereo install, so it wasn't like it was new to me. For those who haven't done this, don't be scared. Pinch the glovebox in, unclip the hydraulic thing from the glovebox and pull the glovebox out. There are 4 screws and a clip that need to be removed, but then you can route any wire you want! (The green/black wires are my serial cable, which stopped working leading to this project)
10 - Behind the stereo area (which is where I have my gauges, you might have a different setup), the red wire was soldered to the white analog wire, and while I was there I relocated the UEGO ground. Ever since I installed it, there was a high pitched whine that irritated the hell out of me but I couldn't be bothered to open this up again. It was originally grounded to the stereo ground, I simply relocated it to a bolt [10mm] (visible in the picture).
11 - Reinstalled the gauges and trim, and done!
Part II
Now that we have an input into the ECU, we need to actually record from it! Our outline is: disable rear O2 sensor, setup EvoScan to record input, log away!
1 - Disabling the rear O2 sensor is done by toggling bit.1 of ECU Options #2. Simply open up your ROM in ECUFlash, find the table "ECU Options #2" and use the "[" key to toggle bit.1 . This updated ROM needs to be flashed to the car. This "Disable" of the O2 sensor DOES NOT necessarily mean you won't get CELs. What we really need is an O2 simulator patch, which is not yet available for the X. I have a CEL, but it doesn't really matter, the future will get rid of that for us.
2 - EvoScan time! First, we need to do some math. Find the documentation for you gauge/wideband, we need to determine the formula that relates the analog voltage to what the AFR is. Look at the documentation, if it lists a transfer function, that's what we want. If not, find the formula yourself by looking at the 0V and 5V AFR and working it out.
For the new AEM Analog WB Gauge, AFR = 2.375*V + 7.3125
For my AEM UEGO Gauge, AFR = 2*V + 10.
This is almost the formula EvoScan needs. We can't input "V" into EvoScan, we need it to be an ECU parameter. Fortunately, we just tapped into the ADC! Therefore,
V = 5*ADC/1023
In my 52680020 ROM, the ADC Memory Address is a 2byte value at 0x80934E.
After testing out the new logging parameter, I had to adjust the formula a bit to get it to actually match the proper gauge output. My output was reading too high, so I had to offset the calculation slightly. My final formula and information is shown in the pictures.
Therefore, what we actually put in EvoScan looks like this. To get this screen, select the 2008 Mode23 USDM EvoX from the dropdown box, right click where the logging items are and edit. Click Add New at the bottom, and enter the details.
3 - Finally, logging time!
I ask if the front 02 sensor would work because it will make it easier to get to for wiring purposes.
Now to all I do not have an EVO X. I got 2008 Lancer ES (with Ralliart turbo on it). So unfortunately its a Cali spec model and has 3 02 Sensors. One was for second cat that was replaced with downpipe. I still have all three plugged in. 2 on down pipe and one on the cat.
I attached a diagram of what I am talking about.
Oh and by the way, for those who want to use ecu pin out instead of struggling under the seat, use this link http://roadraceengineering.com/evox/...-ecuwiring.htm
Newbie
Joined: Jun 2008
Posts: 49
Likes: 0
From: NC
Just a though. Im still researching it.
the stock front02 runs of a 0.5volt signal, meaning the ECU expects a 0.5+whatever NB response...
I doubt your replacement can do that... unless it has a seperate ground for the NB output
I doubt your replacement can do that... unless it has a seperate ground for the NB output
Newbie
Joined: Jun 2008
Posts: 49
Likes: 0
From: NC
It does. I got prosport AFR gauge kit. It comes with WB and NB ground outputs. Which works for me, because I will allow me not to drill any more holes in the exhaust and just swap the stock o2 with WB and use the NB signal from it to go to the oem front o2 senosr plug.
So I finally got around to tapping my AEM Digital WB Gauge into the factory wiring following this howto. I opted to completely remove the factory o2 sensor and cut the yellow wire to directly connect to the analog out wire from the gauge. I verified logging showed changes if it was connected or disconnected and that aspect looks correct in EvoScan.
When at idle and using the shown equation in post #1 of this how-to I am logging around 10.9x to 11.2x AFR when the serial output shows 14.6-15.2 range. Algebra isn’t my best subject anymore so these equations I generally understand but not completely. I played with the numbers and ended up with the following “2*(24.5*x/1024)+10” which got me about perfectly on par with the serial output I see in EvoScan but only at idle. When the AFR’s go leaner say 16.5 on the serial output the analog logged value with be about .3 to .4 leaner and when richer the exact opposite, meaning its .3 to .4 richer than the logged serial output. This isn’t linear and I am wondering if it is my equation that’s the cause possibly.
Logging the voltage EvoScan shows 1.8x-2.06 volts (using the provided equation of “0.01952*x”) and when using a multi-meter I see the normal 2.3x-2.5x swing I would expect considering the AFR and what AEM says the voltage references are. So the voltage to the wire is correct as far as I can tell. The car is unmolested so this is the very first wire that has been cut in the car so no rats nest of audio stuff etc. to worry about. I do have 3 gauges altogether but I don’t see that being the issue as nothing ties into this o2 wire and the analog output from the gauge looks 100% correct.
I am running ROM 56890010, logging address 238086B1 using 1 byte logging, Periphery Bit.1 set to off (“0”), and tried P0139 DTC disable on and off.
When at idle and using the shown equation in post #1 of this how-to I am logging around 10.9x to 11.2x AFR when the serial output shows 14.6-15.2 range. Algebra isn’t my best subject anymore so these equations I generally understand but not completely. I played with the numbers and ended up with the following “2*(24.5*x/1024)+10” which got me about perfectly on par with the serial output I see in EvoScan but only at idle. When the AFR’s go leaner say 16.5 on the serial output the analog logged value with be about .3 to .4 leaner and when richer the exact opposite, meaning its .3 to .4 richer than the logged serial output. This isn’t linear and I am wondering if it is my equation that’s the cause possibly.
Logging the voltage EvoScan shows 1.8x-2.06 volts (using the provided equation of “0.01952*x”) and when using a multi-meter I see the normal 2.3x-2.5x swing I would expect considering the AFR and what AEM says the voltage references are. So the voltage to the wire is correct as far as I can tell. The car is unmolested so this is the very first wire that has been cut in the car so no rats nest of audio stuff etc. to worry about. I do have 3 gauges altogether but I don’t see that being the issue as nothing ties into this o2 wire and the analog output from the gauge looks 100% correct.
I am running ROM 56890010, logging address 238086B1 using 1 byte logging, Periphery Bit.1 set to off (“0”), and tried P0139 DTC disable on and off.
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From: Edmonton, Alberta
So I finally got around to tapping my AEM Digital WB Gauge into the factory wiring following this howto. I opted to completely remove the factory o2 sensor and cut the yellow wire to directly connect to the analog out wire from the gauge. I verified logging showed changes if it was connected or disconnected and that aspect looks correct in EvoScan.
When at idle and using the shown equation in post #1 of this how-to I am logging around 10.9x to 11.2x AFR when the serial output shows 14.6-15.2 range. Algebra isn’t my best subject anymore so these equations I generally understand but not completely. I played with the numbers and ended up with the following “2*(24.5*x/1024)+10” which got me about perfectly on par with the serial output I see in EvoScan but only at idle. When the AFR’s go leaner say 16.5 on the serial output the analog logged value with be about .3 to .4 leaner and when richer the exact opposite, meaning its .3 to .4 richer than the logged serial output. This isn’t linear and I am wondering if it is my equation that’s the cause possibly.
Logging the voltage EvoScan shows 1.8x-2.06 volts (using the provided equation of “0.01952*x”) and when using a multi-meter I see the normal 2.3x-2.5x swing I would expect considering the AFR and what AEM says the voltage references are. So the voltage to the wire is correct as far as I can tell. The car is unmolested so this is the very first wire that has been cut in the car so no rats nest of audio stuff etc. to worry about. I do have 3 gauges altogether but I don’t see that being the issue as nothing ties into this o2 wire and the analog output from the gauge looks 100% correct.
I am running ROM 56890010, logging address 238086B1 using 1 byte logging, Periphery Bit.1 set to off (“0”), and tried P0139 DTC disable on and off.
When at idle and using the shown equation in post #1 of this how-to I am logging around 10.9x to 11.2x AFR when the serial output shows 14.6-15.2 range. Algebra isn’t my best subject anymore so these equations I generally understand but not completely. I played with the numbers and ended up with the following “2*(24.5*x/1024)+10” which got me about perfectly on par with the serial output I see in EvoScan but only at idle. When the AFR’s go leaner say 16.5 on the serial output the analog logged value with be about .3 to .4 leaner and when richer the exact opposite, meaning its .3 to .4 richer than the logged serial output. This isn’t linear and I am wondering if it is my equation that’s the cause possibly.
Logging the voltage EvoScan shows 1.8x-2.06 volts (using the provided equation of “0.01952*x”) and when using a multi-meter I see the normal 2.3x-2.5x swing I would expect considering the AFR and what AEM says the voltage references are. So the voltage to the wire is correct as far as I can tell. The car is unmolested so this is the very first wire that has been cut in the car so no rats nest of audio stuff etc. to worry about. I do have 3 gauges altogether but I don’t see that being the issue as nothing ties into this o2 wire and the analog output from the gauge looks 100% correct.
I am running ROM 56890010, logging address 238086B1 using 1 byte logging, Periphery Bit.1 set to off (“0”), and tried P0139 DTC disable on and off.
The equation I originally posted was "theoretical". I've since changed mine to a much more accurate version.
What I did to get it more accurate was log both rear adc (the raw value, 'x') and the serial connection I had. I then found the best equation to match my recorded values.
I can post my value, but I can't be sure your car will be exactly the same. I'll check when I get home (remind me if I forget!).
Glad it is working!
The equation I originally posted was "theoretical". I've since changed mine to a much more accurate version.
What I did to get it more accurate was log both rear adc (the raw value, 'x') and the serial connection I had. I then found the best equation to match my recorded values.
I can post my value, but I can't be sure your car will be exactly the same. I'll check when I get home (remind me if I forget!).
The equation I originally posted was "theoretical". I've since changed mine to a much more accurate version.
What I did to get it more accurate was log both rear adc (the raw value, 'x') and the serial connection I had. I then found the best equation to match my recorded values.
I can post my value, but I can't be sure your car will be exactly the same. I'll check when I get home (remind me if I forget!).
Currently, it's nothing I feel is safe to considering using over the serial stream at this point which I hope to eliminate eventually as the wire is just unsightly.
I still don't understand why EvoScan shows a .5x voltage variance less than what is actually at the wiring when I look at it with a multi-meter... Hoping someone has an idea on this as that would probably make the original equation close to accurate.
Newbie
Joined: Jul 2010
Posts: 16
Likes: 1
From: Colorado
Anything to get it accurate would be great, so yes please post what you are using as I am sure others will find it very beneficial also.
Currently, it's nothing I feel is safe to considering using over the serial stream at this point which I hope to eliminate eventually as the wire is just unsightly.
I still don't understand why EvoScan shows a .5x voltage variance less than what is actually at the wiring when I look at it with a multi-meter... Hoping someone has an idea on this as that would probably make the original equation close to accurate.
Currently, it's nothing I feel is safe to considering using over the serial stream at this point which I hope to eliminate eventually as the wire is just unsightly.
I still don't understand why EvoScan shows a .5x voltage variance less than what is actually at the wiring when I look at it with a multi-meter... Hoping someone has an idea on this as that would probably make the original equation close to accurate.
what i did was measure the voltage at 2 or 3 points, (you don't have to measure voltage, only if you are thorough like me, the afr value on the gauge will suffice for accuracy)
so use 14.7 like discussed before, get the x value from evoscan, and the voltage from the white analog wire. then get the free air value by unscrewing the o2 sensor and reading x value in open air and the voltage. the further away the two points are the better. plus these two values are absolute.
so mine ended up being a parabolic curve, to check that - divide the volts/x value at each of the two measurement points, if they are not equal, then you do not have a linear relationship.
i.e. - mine were 2.422/495= 0.00492 at 14.7AFR and 3.795/770 = 0.00489 at 17AFR
so my line is not linear, the slopeof a line is y = mx +b where m is constant slope... to solve this the easy way...
wolframalpha dot com
enter the following in the box - parabola (x value, AFR),(x value, AFR)
i entered mine as ... parabola (495,14.7),(506,14.8),(770,17)
the solution will be a curve, it won't look right cuz its not zoomed in but just go to the equation box. and click on the equation that looks like this, but obviously yours will be slightly different.
y = -2.75482x10^-6 x^2+0.0118485 x+9.51
you'll get another screen that displays the curve in more detail
scroll down to the equation in alternate forms and click the lower left hand dog ear to get copyable text, choose the one that is similar to this form
x (0.0118485-2.75482x10^-6 x)+9.51
to convert #*10^-6, each -1 equals a decimal shift to the right
i.e
2.75482x10^-6 = 0.00000275482
then just adapt it for use in evo scan like so
x*(0.0118485-0.000002755*x)+9.51
and your AFR values will be exact throughout the entire curve.
***added info to answer any possible questions-
I forgot to mention a few things, first is that if you can find 3 points instead of just 2, the results of the curve will be more accurate, also it will prevent any possible chance of the vertex being placed between the two points, which would severely screw up your resulting equation.
also try to measure these values with the car running or at a voltage of near 14v in the system, like with a charger attached to the battery as the readings for x will vary since it is directly proportional to voltage seen from the analog output,
second is that if you end up having a linear equation, we will use the y=mx+b form, where m = deltay/deltax
so m would equal y2-y1/x2-x1 where y is AFR and x is x value from evoscan. the offset b will have to be found by inspection from logging in evoscan with the new formula. it should be around 10 ish though.
Ok, to answer why we measured voltage, it is more accurate, and if you choose to use that instead of AFR to solve for the equation, you will have to develop a relationship between the AFR value and the voltage value to offset the formula, so your + xxxx value on the end will be diffferent to get the proper afr value. This is up to you, but my values are pretty close and .1 difference from rounding up or down does not really bother me when logging.
note: a drawback of computational delay which is in milliseconds may occur depending on the processor power of the laptop you are using.
plugging the laptop into an inverter while logging to maintain full power usage is recommended to minimize any lag in the afr values vs rpm curve. especially during spool up when the values and load cells transition rapidly.
hope this helps
Randy
Last edited by nukerj; Feb 1, 2012 at 04:15 PM. Reason: added some clarification
does anyone have a wiring diagram of the wiring under the passenger seat or where i can buy one? there are 3 harnesses under that seat and i would love to just tap into a 12v+ there and ground to the chassis that way my entire install leaves a tiny foot print.
EDIT: no longer needed. i purchased vehicle manual from alldatadiy.com for $10. i didnt find a switched power under the seat so i just ran it to the passenger side kick panel.
EDIT: no longer needed. i purchased vehicle manual from alldatadiy.com for $10. i didnt find a switched power under the seat so i just ran it to the passenger side kick panel.
Last edited by momostallion; Mar 1, 2012 at 05:36 AM.