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Mugder
4th December 2022, 09:35 AM
Hi all. Recently bought a 1994 GQ TB42 Manual with EFI and gas conversion. Currently tidying up the engine bay. Hoping someone can tell me about the relays in the engine bay next to the battery under the black cover.
Specifically interested in the ones circled in the pic. Top right corner brown relay, unused blue relay socket and the blue relay mounted to the guard with the silver wire wrap.

thanks heaps. Everything seems to be working fine but just curious for future reference before I put everything back together.

Mugder
4th December 2022, 09:38 AM
I forgot to mention there is no power windows on the car or rear a/c. it is an RX model. thanks

mihit
6th December 2022, 04:07 PM
Have an assistant turn the key from "OFF" to "ACC" and feel (finger on relay cover) which ones -click-. Then do the same with key from "ACC" to "ON"... will narrow it down for you.

Or just pull the relays out and see what stops working?

mihit
6th December 2022, 04:08 PM
There will be a colour-coded wiring diagram in a manual, somewhere, too.

Mugder
8th December 2022, 03:28 PM
thanks. i will give that a go. Given it is a manual i had ruled out the Park/Neutral no start relay, no power windows, no rear a/c. ATP / PTC heater also seemed unlikely given some googling to understand what this could be. I will see if I can access a manual. Thanks for responding mihit

mihit
11th December 2022, 11:37 AM
I've got my haynes manual handy...if you tell us what colour wires go to the relays I can tell you what it reckons...

Mugder
30th December 2022, 07:58 PM
Merry Christmas all ... thanks mihit.
details and pics below

First pic is the harness plug that is upstream from the blank Blue Relay Socket and the Brown Relay.
Input wires:
- White with sky blue stripe
- Sky Blue
- Purple
- White with Red Stripe
- White with black stripe

Output (these lead to the relays in question .. downstream)
- Red
- white with black stripe
- white with red stripe
- white with sky blue stripe
- Purple
- white with black stripe
- sky-blue with red stripe

Mugder
30th December 2022, 07:59 PM
864358643686437

Mugder
30th December 2022, 08:01 PM
now for the Brown Relay:

- white with black stripe
- white with red stripe
- yellow with red stripe

- black
- red
- white with black stripe

8643886439

Mugder
30th December 2022, 08:03 PM
Now the Blue Empty relay socket:

- Orange with Blue stripe
- Blue with red stripe
- purple
- white with sky blue stripe

864408644186442

Mugder
30th December 2022, 08:05 PM
last is the Blue relay. This is the one at the bottom of the very first pic at the start of this thread (the one with silver tape on the wires). It is mounted to the guard.

- White with red stripe
- white with sky blue stripe

- sky blue
- Black

thanks very much ... hope someone can identify these.

86443

mihit
2nd January 2023, 12:16 PM
Blue relay is for an "electric cooling fan" (radiator I guess)

Pretty confident brown relay is on alternator circuit.
Empty harness I'm happy to ignore but feel free to chuck a relay in and see what happens.

I did take pics of the relevant pages, I will upload them when I can.

mihit
2nd January 2023, 12:18 PM
Just spotted it. Empty harness is Rear Aircon.

Mugder
21st January 2023, 11:17 AM
Excellent thanks very much mihit much appreciated

Mugder
29th March 2023, 05:23 PM
FYI .. looks like the Brown relay is part of the starter circuit. If I pull the relay out the car won't start ... no sound, completely dead.

Mugder
1st April 2023, 05:49 PM
cancel that ... car still starts and runs with brown relay pulled