Thread: About to give up after seat ECU repair

so I pulled the seat out again, and opened up the seat ecu box, and looked at the relays that work when I use the mirror actuator, and those that don't.


I found the number 5 relay is the one that doesn't activate. when I push it together, the mirror moves down. there are two other relays on the board that activate, just not the number 5. Hoping I might be able to just pull this one out and get a new one somewhere and put it in. I sprayed it with contact cleaner and that didn't seem to work.

Probably the coil has gone 'open circuit'. (wire broken somewhere). Or the copper track between that and the driver IC , one of the 16 leg black thingies is broken.
Least likely is the driver IC is at fault, on that output.

- All of the above assuming your DOWN button is working perfectly...

I am 99% sure the mirror down button is working, as two other relays turn on when I move it down. Just not relay number 5.


Is there a way I can test this relay while on the circuit board?

Disregard post, retracting my bad advice

Do you have a multimeter? Coils rarely go open but they do. It is more likely it has latched in the off position IF the relay is faulty. Also to make a motor drive in different directions (forward and backward) you need 2 relays. If only one relay is faulty it is very possible you could only drive in one direction.

Honestly mate you are going to struggle without a multimeter or at least a test light. I'm busy until after ANZAC Day weekend, but if you PM me we can organise a time and i will look at it with you.

Originally Posted by Crash76

I am 99% sure the mirror down button is working, as two other relays turn on when I move it down. Just not relay number 5.


Is there a way I can test this relay while on the circuit board?

Can you get me a circuit diagram of the mirror and seat ECU?

I do have a multi meter, but cant find an actual diagram of the ECu board. The RAVE manual has some type of wiring diagram, but not that easy to follow.


When I test the soldered stubs on the bottom of the relay, I get power at all but one. When I move the mirror button down, two relays activate, and the power at one of the soldered sections goes from above 12v, down to about 9v, then back up and down as the other relays click on and off.


When I do the same test on the other mirror relays, the same occurs except the volts drop down to below 3v unti I stop moving the mirror actuator.


The "pole" I guess I would call it where the voltage drops is the one that leads from the IC I think it is called. All the tracks look perfect in that area, and I get over 12v before using the mirror switch.

Originally Posted by Crash76

I do have a multi meter, but cant find an actual diagram of the ECu board. The RAVE manual has some type of wiring diagram, but not that easy to follow.


When I test the soldered stubs on the bottom of the relay, I get power at all but one. When I move the mirror button down, two relays activate, and the power at one of the soldered sections goes from above 12v, down to about 9v, then back up and down as the other relays click on and off.


When I do the same test on the other mirror relays, the same occurs except the volts drop down to below 3v unti I stop moving the mirror actuator.


The "pole" I guess I would call it where the voltage drops is the one that leads from the IC I think it is called. All the tracks look perfect in that area, and I get over 12v before using the mirror switch.

That is a considerable amount of voltage drop, LUCAS SPECIAL! Depending on how the circuit works and where you have the multimeter probes i'd guess the 3 volt one works better. This is probably the voltage across the relay output contacts that really in an ideal world would be 0 volts when activated and 12 volts when not activated. It is unlikely the IC (Integrated circuit) is the problem.

What you want to measure is the voltage at the mirror end. Make sure you have voltage at the mirror motors when you are meant to. compare each side. I'd expect at least 10 volts at the mirror end.