Car starts on turn of key...not with starter button!!

The Oily Bits S2 Specific Topics
1

Ok, so the other week I had a blonde moment and crossed the terminals on the race battery. This blew 20a fuses going to the ECU (Audi 8P engine converted car) x 2 and also a few 5-7.5a fuses under the access panel.

I sent the ECU off to BB Reman (ECU repair shop) as the 2x 20a fuses would blow constantly and the car wouldn’t start (crank but not fire). Today I plugged the fixed ECU into the car and the 2 fuses no longer blow…and the car starts, but we have a rather strange issue! Now when I turn the key to stage 2, the car will start the moment I disarm the alarm (stock Lotus item). If the alarm isn’t armed, simply turning to stage 2 will start the car.

I’ve tried unplugging the starter button but it still does it…any thoughts? Sounds to me like the wire to the starter button from the ign barrel has a bad contact but I can’t see anything obvious :frowning: Please no laughing or judging my stupid mistake! I know I’m a tit and still can’t believe I did it after 15 years of working on cars…

2

yeah so I’d get the ignition key on the bench and check it works as it should, also have a look at the immob

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3

Ah crap, that sounds like fun (not)…I’m great at soldering wiring up but not so good at testing electrics. Any suggestions on how to test the key and the immob? No idea where the immob is!

All the wiring looks fine from a visual inspection (on the ign barrel and starter button)

4

you got the toyota service manual? wiring diags in there

might be easier to get a replacement switch though

the immob interrupts the start signal when armed

5

The one thing I have spotted is that the wiring to the starter button has been chopped (not by me and fine until the ECU fix). There are 4 wires, green, white/red, black and green. The white/red has been cut and wired directly to the green next to it??

This could become a nightmare if I’m not careful…it’s going to be really hard to get info from the guy who did the engine swap as they went bust a while back.

6

yeah I know that pain:

So are those colours lotus ones, or audi ones?

7

Nice!

Yeah I think the wiring is Lotus and I’m thinking (god knows why) that the hack has been done because of the ECU maybe?

pin on ecu bent out…odd

third wire in, wired to the first…more odd!

8

Ok, so Ive tried all the relays and fuses I can find…it looks like the 4th connector to the starter button (one to trigger the crank?) Has a permanent feed. Can anyone point me to the wiring diagram for the starter button and where that wire goes to (green)

9

drop me a PM with your email :slight_smile: