[Mk2] [Turbo] Re-pin guide for Rev 2 body loom to rev 3 ECU

[DottySkee]

Hi All,


After a few posts on this and a few mistakes on my part, I need to repin my rev 2 body loom at the fusebox and ECU to get the car running.

Told this is pretty simple but before I go swapping things around, I'd like to know exactly what I'm doing before I start (don't want to bodge up the loom).

At the ECU seems easy enough, just the one pin to change called EVP (judging from 2bar tuning guides) but it shows relocating it to a pin that already has duty. So wehre does the wire I'll remove go then?
At the fuse box their guide is a touch confusing for an electrical idiot like me. Does anyone possibly have another guide for the repin of a rev 2 body loom to work with a rev 3 engine or could tell me which pins to relocate to where that would be great.

This guide looks like it's for converting a rev 2 engine to rev 3 as it note new sensors to buy. Don't need this complication for myself, just what to repin on the body loom.


Thanks

[Peter Gidden]

EVP is on the 26 pin ECU plug, which is an engine loom plug, not the 22 pin ECU body loom plug.

[DottySkee]

Ok I got the diagram back to front (counting on my part would help).

So, from the 2bartuning guide (http://www.2bartuning.com/#/resources-mr2/4527157490) on the 22 pin plug, I've got FPR, ECO, ABS (not needed for me as non ABS car) RLY (RLY sounds right actually as one of my faults is a faulty earth on starter relay) to re pin.

However, this guide has pin swapping between plugs, is that right if my engine loom is a rev 3 to match the ECU?

In case you can't tell, this has me thoroughly confused don't quite know where to start

[DottySkee]

Question on the FPR and RLY. The diagram seems to be for converting a full rev 2 loom to fit a rev 3 ECU. I only need to repin the body loom, so what happens with FPR and RLY that show to move between plugs?

Do I just pull FPR out and put the ECO in, leaving that wire out? As the FPR wire will be there on my rev 3 engine loom?

Same for RLY, to take the wire from the 26 pin plug, but that 26 pin plug should be correct already being rev 3 engine loom? What happens in that situation? Should I leave the 26 pin plug as is and put my own earth on the starter relay?

One of my problems is the earth on the starter relay. As is, car gives no CEL and what should be the earth for the starter relay is live. When I put my own earth on the relay, I get a CEL and can crank the engine on the key but I've got no spark. If I get all the other wiring correct on that plug then put my own start relay earth on, should it be good to go?

Once I know it's at a point it SHOULD be going, if I have any other problems I can investigate them knowing I've got it wired up right.

[DottySkee]

Hoping for some help here. Swapped the rev 2 body look back in as from looking at the diagrams we found, it was going to be easier as you said Pete.

Matched it up to a rev 3 loom we have to compare and think its pretty close. There is however a few wires go pins not on the diagram. Plugged it in to see what it does now and see what else is wrong.

Before, turn it to ignition on or start and it wouldn't turn over with no CEL. Now, turn it to just ignitiom on and the starter motor keeps on cranking BUT still no CEL and no spark. So from that, we must have a live in the starter relay when it shouldn't. Any ideas anyone?
Could some kind soul also take a picture of their rev 3 turbo body loom olug that goes into the ECU? Our rev 3 is slightly different from the diagrams we have s9 don't fully trusf it. Could someone take a picture showing what wire go in what pins on their body loom plug so we can compare?

Cheers

[Peter Gidden]

Now, turn it to just ignitiom on and the starter motor keeps on cranking BUT still no CEL and no spark. So from that, we must have a live in the starter relay when it shouldn't. Any ideas anyone?

Sounds like main loom earth to underside of inlet manifold not secure.

[DottySkee]

Now, turn it to just ignitiom on and the starter motor keeps on cranking BUT still no CEL and no spark. So from that, we must have a live in the starter relay when it shouldn't. Any ideas anyone?

Sounds like main loom earth to underside of inlet manifold not secure.

Hi Peter, the main earth to the underside of the inlet manifold is attached and nice and tight, still the same issue.

We worked through the plugs which could be putting load on the starter relay earth. Correct me anywhere our process is wrong.

The starter relay earth wire goes from the relay to the fuse box in the engine bay (white wire with a black trace, correct?). At ignition on, this has 11.5V on it. When at start, the "live" for the relay goes to 11.5V so that side is behaving itself correctly. The earth shouldn't be live at ignition on of course.

So, we decided to pull plugs to check where the live is coming from. When we pull the plug in the fuse box the white/black trace wire goes to (connects to body loom?) and switch to ignition on, we still have 11.5V on the relay earth. The looms however look to have that wire in the same pin position between the rev 2 and 3 in that plug.
When we pulled the other plug in the fuse box, the smaller one, it went to 0V. To us, that makes no sense unless we are missing something, is there repining at the fusebox to do too? I don't remember reading anything about that but may be mistaken.

The only thing we can see on the wiring diagrams where there could be live put on the earth is in "J/B 3" which I'm guessing is a fuse box, noted on the diagrams as behind the glovebox. However, still makes no sense as the dash and body loom are both rev 2 and the car worked with the rev 2 engine in, nothing has been touched down there.

A bit stumped at the moment and feel as if I'm missing something glaringly obvious. Hope the above makes sense too.

[Peter Gidden]

OK, pull starter relay out of relay socket.

Measure voltage at pins in socket with relation to chassis earth:

Ignition off - pin 1 (red) and pin 3 (white/black)

Ignition on (engine should not turn over) - pin 1 (red) and pin 3 (white/black)

[DottySkee]

OK, pull starter relay out of relay socket.

Measure voltage at pins in socket with relation to chassis earth:

Ignition off - pin 1 (red) and pin 3 (white/black)

Ignition on (engine should not turn over) - pin 1 (red) and pin 3 (white/black)

At ignition off - Pin 1 (red) is 0v, pin 3 (B&W) 0V

At ignition on - Pin 1 (red) is 0V, pin 3 (B&W) 11.5V

round to start - pin 1 (red) ~12V, pin 3 (B&W) 11.5V

[Peter Gidden]

OK, pull starter relay out of relay socket.

Measure voltage at pins in socket with relation to chassis earth:

Ignition off - pin 1 (red) and pin 3 (white/black)

Ignition on (engine should not turn over) - pin 1 (red) and pin 3 (white/black)

At ignition off - Pin 1 (red) is 0v, pin 3 (B&W) 0V

At ignition on - Pin 1 (red) is 0V, pin 3 (B&W) 11.5V

round to start - pin 1 (red) ~12V, pin 3 (B&W) 11.5V

OK. Cut the white/black wire a few inches from the relay base. Earth it to the bolt though the relay mounting bracket.

[PW@Woodsport]

The black/white wire is the output signal to the starter solenoid, don't earth that!

Earth the white/black wire.

[DottySkee]

Sorry for the lack of updates, been on holiday.

So I've cut the earth for the starter relay and earthed it. The car now behaves correctly on the key, i.e. only tries to start when turned to start. Still no CEL though and not starting.

I've been all round all the connections again and it's plugged in/earths attached.

Stumped.

[PW@Woodsport]

Trailer it down to me, i'll fix it for free in under an hour, and you can drive it home

[DottySkee]

Trailer it down to me, i'll fix it for free in under an hour, and you can drive it home

Seriously? That would be brilliant. I just need to try and sort a trailer out, Durham isn't too far really.

As long as you show me what I've done wrong

[PW@Woodsport]

Yep no problem, bring your old rev2 engine harness with you if possible