A/C Fan Stays on with key and No start
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Evolving Member
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From: Fort Collins, Colorado
A/C Fan Stays on with key and No start
Hello all, I finally got the AEM EMS in the car and when I turn the key on the AC fan comes on and stays on. I do not know a lot about tuning however I was starting to get somewhat comfortable with the stock ecu. The AEM program is taking me some time to understand though. I am trying to get this running on an OmniPower 4 bar MAP with E85 and FIC 2150cc injectors. Where can I go to get a good base start up MAP? I have not ran the car on speed density with the stock ecu but I was planning to switch it over with the AEM. Any help is appreciated!
Evolving Member
Joined: May 2005
Posts: 100
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From: Santa Monica, CA
Do you have a Series I EMS (30-1313) or Series II (30-6310)? Either way, you must load a base calibration before anything will work correctly. All base calibrations are included with the free software available at www.aemelectronics.com.
The fan will fun full speed if it does not receive a signal from the PWM fan controller, as it's set up as a Normally-Closed circuit. It's probably not getting a signal since the EMS doesn't have an appropriate calibration loaded.
If it's a Series II EMS, there's a wizard for the OMNI 4-bar MAP. If it's a Series I, change these values under Setup --> Sensors --> Manifold Absolute Pressure --> Options - MAP.
MAP Min Volts 0
MAP Max Volts 4.8
Load Offset 0
Load Scalar 4
OR, just take it to a tuner. In fact, yeah, just do that.
The fan will fun full speed if it does not receive a signal from the PWM fan controller, as it's set up as a Normally-Closed circuit. It's probably not getting a signal since the EMS doesn't have an appropriate calibration loaded.
If it's a Series II EMS, there's a wizard for the OMNI 4-bar MAP. If it's a Series I, change these values under Setup --> Sensors --> Manifold Absolute Pressure --> Options - MAP.
MAP Min Volts 0
MAP Max Volts 4.8
Load Offset 0
Load Scalar 4
OR, just take it to a tuner. In fact, yeah, just do that.
I had the exact same problem. Make sure that you have all your sensors wired up correctly. I had two wires mixed up for my map senor and the fan would just come on, I wouldn't be able to connect to the ecu, and the car wouln't start.
Bringing this back up.. wanted to give some info.. for anyone in the future that runs across this problem (like I did w/ my v2 ems).
Main fan would stay on... before starting, after starting.. until key off.
Changing the inputs made no difference... even cut the wires that are supposed to control the fan finally.. still on
After hours of troubleshooting, testing, unhooking all my relays that run the fuel pump/coils etc (my setup is unique) I finally determined it was nothing I had done (just wanted to make sure). Something was powering the fan from the ECU (stock ecu didnt have this issue).
So my solution was to tap into the fuse box, and take control over the wire that turns on the fan relay. I ran a wire to that, and to the aem ems.. tapped into pin 31 on the ecu (have to add a connector to the plug)... then in the software, you tell Idle8 to run your Radiator Fan 1.. set it up how you want it, temps etc.. and bam.. good to go.
I don't know what was to blame in my case.. but if someone else runs across this issue and can't figure it out.. a solution like this might come into play!
Main fan would stay on... before starting, after starting.. until key off.
Changing the inputs made no difference... even cut the wires that are supposed to control the fan finally.. still on
After hours of troubleshooting, testing, unhooking all my relays that run the fuel pump/coils etc (my setup is unique) I finally determined it was nothing I had done (just wanted to make sure). Something was powering the fan from the ECU (stock ecu didnt have this issue).
So my solution was to tap into the fuse box, and take control over the wire that turns on the fan relay. I ran a wire to that, and to the aem ems.. tapped into pin 31 on the ecu (have to add a connector to the plug)... then in the software, you tell Idle8 to run your Radiator Fan 1.. set it up how you want it, temps etc.. and bam.. good to go.
I don't know what was to blame in my case.. but if someone else runs across this issue and can't figure it out.. a solution like this might come into play!
Main fan wich is radiator fan is controlled by PW user table on ls9 output on AEM series 2 with 1.24 calibrations, if you have the 2.02 firmware there is no ls9 anymore (3.2 aem tuner) so the main fan will be not controlled, so you have to move to ls1 and assign the output to the PW user table to control de fans duty cycle
hope this helps
hope this helps
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Main fan wich is radiator fan is controlled by PW user table on ls9 output on AEM series 2 with 1.24 calibrations, if you have the 2.02 firmware there is no ls9 anymore (3.2 aem tuner) so the main fan will be not controlled, so you have to move to ls1 and assign the output to the PW user table to control de fans duty cycle
hope this helps
hope this helps
Evo 8 - What is happening is the new firmware de-selects some output pin functions. To fix this, pull up your User 1 PW output and set it to LS2. You will also need to turn ON User 1 PW Inv. Once you do this, the rad fan should function like normal.
Evo 9 - For an EVO 9 the fan control is on LS9 instead of LS2 like the EVO 8. Other than that it’s the same. LS9 was removed on our 2V02 upgrade for some reason that was not implied. If you want to keep the factory PWM fan control, you could move the wire from pin 18 (LS9) to pin 26 (LS2).
I brought this issue to AEM's attention after the V2.02 release for Evo 8 and 9's, here is the response I received from them after an engineer looked into the issue.
Evo 8 - What is happening is the new firmware de-selects some output pin functions. To fix this, pull up your User 1 PW output and set it to LS2. You will also need to turn ON User 1 PW Inv. Once you do this, the rad fan should function like normal.
Evo 9 - For an EVO 9 the fan control is on LS9 instead of LS2 like the EVO 8. Other than that it’s the same. LS9 was removed on our 2V02 upgrade for some reason that was not implied. If you want to keep the factory PWM fan control, you could move the wire from pin 18 (LS9) to pin 26 (LS2).
Evo 8 - What is happening is the new firmware de-selects some output pin functions. To fix this, pull up your User 1 PW output and set it to LS2. You will also need to turn ON User 1 PW Inv. Once you do this, the rad fan should function like normal.
Evo 9 - For an EVO 9 the fan control is on LS9 instead of LS2 like the EVO 8. Other than that it’s the same. LS9 was removed on our 2V02 upgrade for some reason that was not implied. If you want to keep the factory PWM fan control, you could move the wire from pin 18 (LS9) to pin 26 (LS2).
