144mph

iTrader: (19)

I'm trying to follow the factory service manual (FSM) and test the starter relay, but the test result keeps coming up the opposite of what one would expect. Furthermore, when I test out two other relays, the test is consistent with the results from the starter relay, suggesting that the relay in the car is not faulty, but also not in alignment with what the FSM says.

Here is the test as described in the FSM.


Here are the relays I'm using. The one on the left is a new relay purchased from the auto parts store with a similar pinout to the factory starter relay. The middle is the factory relay and the one on the right is a relay I had laying around in my electrical wiring bin. The pinouts on the large relay on the right are slightly different to those other two in arrangement but the names of the terminals (30, 87a, 86, 87, 85) are all just as the tiny imprints on the factory relay undercarraige.


The test procedure is pretty straight forward. You connect pin 1 to 12v source (battery) and pin 3 to ground. The resistance between pins 2 and 5 should then be less than 2 ohm. When the pins 1 and 3 are disconnected, the circuit between 2 and 5 should be open, or infinite resistance. What I'm seeing, on all three relays, is 1 ohm resistance between pins 2 and 5 when the pins 1 and 3 are not connected to a 12v circuit and when they (pins 1 and 3) are connected, there is a click (the solenoid activating) and then the connection between pins 2 and 5 open, meaning there is no current flow at all between them.

Bottom line is that this car won't start and I get a click and lights dim with no crankage whatsoever. I've gone through the FSM checks and I'm stuck on this one. Next up will be the clutch switch (currently jumped, so I doubt that's the issue) and the ignition switch. If that doesn't work, I'll probably need to trace the smaller wire coming off the starter back to it's source and replace that wire as it looks vaguely cruddy. I've already verified the voltage at the starter, the starter and the battery.

144mph

iTrader: (19)

Today, I noticed that the test procedure in the manual has pin 1 connected to 12v and pin 3 to ground. However, in the circuit diagram (see below), it would appear that pin 3 normally connects to the ignition switch and pin 1 connects to ground. I don't know what to make of that, since the the resting state of the solenoid should be open and when energized it should be closed. Perhaps I'm not interpreting the dashed lines on that diagram properly.

I can get the car to crank if I jump pin 5 directly to the battery terminal in the engine bay. That eliminates the chance that there isn't enough power in the battery to turn the engine or if there is a mechanical issue preventing the engine from turning over. It also confirms that the starter is indeed good. Replaced the starter solenoid wire running from connector B-14 in the engine bay as it looked a little suspect. Then tested to see if the solenoid wire was getting any voltage when the ignition is turned to start, per Wazzelby's thread on here. There was no voltage at all, which means that the problem is upstream of that wire.

The diagnostic test for the starter switch checked out okay. Then jumped pin 11 on the C-129 connector in the driver's kick panel to ground so that should bypass the clutch switch, in case that was the problem. No joy. I couldn't get the clutch switch out or get the probe in there to test as it would take some kind of contortionist with tiny little fingers to manipulate in that zone full of sharp metal edges ready to slice up fingers. Not ideal working conditions in a garage barely heated to above freezing.

Here's a copy of the circuit diagram. I replaced the bit between B-14 and B-21 with a piece of 10 gauge wire, just to be sure it can handle the load.


Suggestions welcome...

144mph

iTrader: (19)

Another update here.

I followed the above circuit diagram and individually traced each of the wires in the drawing to each subharness connector. Everything checked out as one would expect. This lead me back to the starter relay.

Nobody had a replacement starter relay in stock, except for the first store I described in post #1, which had a relay that tested exactly like the one I pulled from the car.

Based on my understanding of what the relay was meant to do and how it should operate, I took a chance and wired in a different random relay in my parts bin that was similar but not identical to the one in post #1. Difference being that this one tested similar to how the FSM describes the relay should operate. Upon connecting this new Bosch relay, the car cranked on cue. So now the car starts and runs.

As I'd like to get the relay box cover back on, I want to put the correct form factor relay back in the car but I'm a little hesitant to purchase a new relay when the one from the auto parts store and the one which I have that is testing opposite doesn't work.

Can someone with a car that runs and starts follow the FSM test procedure in the first post to verify that their starter relay operates that way?

Peter2F

It seems that the Mitsubishi relay is not a ISO standard relay.
If you ignore the numbers and look at the Pictures instead,
In the manual, the coil ( which activates the relay ) is between 1 and 3.
But the ISO standard ( also the relay you have to your left in your picture ) the coil is between 1 and 2.
So you would not get the same result if you just go by the numbers.

Peter

144mph

iTrader: (19)

Peter, thanks for the response. A 'standard' relay (not sure if it's an official ISO standard or not, but it matches with any diagram of a relay I've come across) looks like the bottom portion of the below pic.



It would seem that the pins 1 and 3 in the factory manual are similar to 85 and 86. pin 2, which receives 12v from the starter switch is 87. pin 5, which runs to the starter solenoid is 30. Finally, pin 4, which isn't used on the car is 87a. This is confirmed by the tiny imprints on the bottom of my factory starter relay. When the starter switch is turned, it energizes the coil and the connection is made between 12v from the starter switch and the starter solenoid, causing the engine to crank. This follows the logic of the starter relay test described in my first post.

The problem I had is that the existing starter relay I had tested the opposite, meaning that 2 and 5 had continuity when there was no current between 1 and 3 and when the coil was activated (i.e. current between terminals 1 and 3) the connection was broken. This also happened on a new starter relay I purchased from the auto parts store. It took a 'standard' relay from my spare parts bin to get the car running.

My car starts and runs okay now, but I'm wondering if someone with a running vehicle can check their starter relay following the diagnostic procedure in the FSM to see if it matches up. I'll probably end up purchasing a new starter relay from the dealership so that I can put the cover back on there, but I'd like to make 100% sure my part is bad before I do that.

burton402

Can you verify where pin 4 goes exactly? I'm wondering if pin 4 makes the relay act normal as far as the FSM goes. If pin 4 is grounded or hot, maybe it will make the relay act opposite of what it is testing. I'm dealing with a similar problem. I tested mine and have the same result as you. The only difference between my problem and yours is that I have zero power through the whole car. My batt is brand new and connections are good. I relocated to the trunk and it worked fine for almost 3 months, now I have noth. Where I tied into the alternator fusible link I measure 4 volts. However, when I disconnect the main batt feed I get 12.6 volts. When I do get power and go to start, everything just turns off again. Let me know what you come up with as far as the relay.

144mph

iTrader: (19)

Pin 4 on the factory starter relay isn't used. If you look closely, you'll see that the spade connector on the relay doesn't have the same friction marks as the others because it doesn't contact anything when pressed into place.

The fact that you're reading 4V at the engine fuse box with the batter connected indicates there's a big voltage drop from the battery in the trunk of the car. I'd inspect / replace the cable that you're using to connect between the battery and the junction with the alternator, fuse block and starter power wires. Perhaps it's degraded over the past three months. What size and type of cable are you using for that run? It needs to be at least 4 gauge to handle the current draw over a ~5 meter span.

burton402

Cable is brand new and I'm running 2/0 both hot and ground. I had power for a second and then as soon as I hit start, everything dies. I disconnected everything at the factory junction block and it read 12.6V at the main battery cable. When I put it back together and I had power, but then like I said it went haywire again and I haven't looked at it since then. Minus the junction block, would a bad starter or bad alternator do this? The only reason I don't think it isn't the alternator is the fact that when I disconnect the alternator nothing changes, but I haven't played with it since. Any headway on your car at all as far as the relay?

michaelrc51

iTrader: (37)

You have some kind of short or draw going on.

Hard to help you diagnose anything without all of the information....

144mph

iTrader: (19)

A bad starter or alternator wouldn't cause the voltage readings to jump around on the junction block or make you see a big differential between the voltage measured at the battery terminals in the trunk and the engine bay terminals.

When you perform the diagnostic check on the relay, does it come out okay (i.e. according to the factory manual)?

Reading you response again, I think it would help if you clarify what you mean when you say that ‘it went haywire’ after you ‘put the junction block back together and I had power’. Also, when you say ‘I hit start, everything dies’ – does that mean that when you turn the ignition switch into the start position, then the dash lights go out or is it something more? Is there a click or clicking from the engine bay? The dash lights and almost everything in the interior is supposed to turn off to conserve current draw for turning over the engine, but they should come back on when the key is in the acc or run position. If there’s any question about the alternator or starter, I’d take them off and have them checked just to rule out the possibility. I know the alternator is a pain in the *** to get at, but the starter isn’t bad at all.

I got mine running by substituting a spare relay in the place of the factory one. I’m still not sure why the factory relay or one from the parts store didn’t work. I’m out of the country now until July, so I can’t really troubleshoot it further until then. I’ll probably end up buying a new starter relay direct from Mitsubishi and run some diagnostics on it because I’ve already independently traced all the wires in the circuit to verify that’s as it should be. I don’t want to be using the current workaround longer than I have to because the cover for the relay panel doesn’t fit on with the oversized relay and wire leads.

burton402

When I put the junction back together I had power like you normally would, ex. Dome lights come on when door opened. Well I decide to try and start it, turned the ignition switch to start and power turns off like if someone disconnected the battery. I hear an audible click when key is turned to start and then power goes out. When I returned the key to the off position there was zero power. No dome lights, no door ajar light. It was like it was completely dead but the battery is at 12 plus volts like normal. The battery is about 3 months old.

burton402

All fuses are good. Checked twice and I'm going to check a third time just to make sure and do voltage drop test on everything from a to z.

burton402

Turns out to be just a faulty battery ground. Thanks for any pointers.

blowngasket

iTrader: (4)

Your original problem is the same as mine, The relay wasnt getting a ground signal the ground sinal goes thought connector C22,C126 and C127 clutch safty switch my switch wasnt bad but the ground was jacked up some how and causeing a short sometimes it would start sometimes it wouldnt. I just rewired the relay to work as i want it to, a basic safty to save the igniton switch from dying, The other red/black wire feeds the ECU to tell the ECU im trying to start And yes the immobilzer too works with the ECU to feed that signal and instead of shorting it out allowing it to flow,