Electrical: 3b not starting.

[WidowmakerS2]

I was planning on starting the 3b up today, after some time dealing with other things on the car. The engine is from a 92' S2, the car is a 90' CQ.
On turning the ignition key, the starter does not turn, and there is no noise from the fuel pump.

Briefly what has been done:

Battery wiring : (battery moved to the back)
1x 2 gauge to earth
1x 2 gauge to engine bay, where it splits into 2x25mm2 and 1x20mm2
->
1x25mm2 for the starter
1x25mm2 for the alternator
1x20mm2 for CEP (L30 terminal)

Fusebox:
Big multiplug to 'B' (Wrong on first try, but didn't make a difference)
Green/Black wires to 87a
Red wire to L30
Red/black wires to M30ac
Gray/green to O.
All fuses OK.

Starter:
1x25mm2 (Measured battery voltage at connection)
1x white plug (Different wiring than the original one. The starter has two pins)

Alternator:
1x25mm2 from battery
2x15mm2-ish cables to CEP.
1xsmall blue eyelet.


Both earth points on the intake manifold is good.
Earth point on A-pillar is okay.

[s2driveruk]

is the battery in good shape...mine was only giving about 10Ah output hence seriously poor starting

[WidowmakerS2]

The battery is brand new. Upon turning the key i can hear a relay clicking two times, and then nothing.

I'll check the engine earth strap today, but that doesnt stop the fuel pump from running

[add]

alarm/immobiliser?

[WidowmakerS2]

Yeah, actually its got a DEFA alarm/immo. And that could explain a lot!
The DEFA's just cuts everything, don't they?

[add]

Yeah,i think it cuts fuel & starter,i've had the problem you have in the past,turned out the plug was loose

[WidowmakerS2]

Hmm, the defa is not the cause here. The defa immobilizer function is disabled (no wires).

Starter runs when +12V is given to the solenoid pin.
There is no voltage at solenoid plug with ignition ON.


I'm back to thinking it could be a fusebox problem.
What in there gives switched +12V to the fuel pump and starter solenoid?

[WidowmakerS2]

Where's the wiring gurus at?

[WidowmakerS2]

Allright, think I might have used the wrong schematics for wiring the fusebox.

Fuses:
20A = Red+Red/white
15A=Blue/Black+Green/Black
15A=Green/Black+Blue/red
20A=Blue/Black+Blue/Black+ Black

5A= Gray/red+gray/green

Will have to recheck. Going to try to connect all 4 plugs to +12V.

[S2central.net]

I'll ping some thoughts later but here's some initial things...

You might have deleted the immo but has all the factory wiring been restored for the feed for solenoid thru the ignition switch and that B plug ?

Ecu has to see 12v power and good rpm signal before it activates fuel pump. The immo might be wired to ecu supply and or fuel pump. I need to have schematics in front o me to advise further. I am good but not that good - lol.

[S2central.net]

Use the MY92 coupe 3B diagrams from wiring page of s2central.net. Please direct any immo questions to me personally as I don't like giving that info in public forums for obvious reasons.

[WidowmakerS2]

I was hoping for a reply from you!

Only problem with using those schematics is that the wire colors are wrong about 50% of the time. I'm closer to ABY on the colors it seems.

Pretty sure the immo has never been operative. Guess that's a good thing, seeing how rubbish all the connections are (insulation tape). I've got wire colors for 1 inch, and then whoever installed it has used pretty much whatever was lying around it seems.

[S2central.net]

See track 4 on http://www.s2central.net/S2_Schematics/D/D34.PDF

That black wire to the starter solenoid comes via B50A on the big black plug in the fusepanel. Check you have the jumper or relay working in position #8 of course or the 'start' signal from switch D never gets to the solenoid.

S24 & S28 are fed from green/black wire at 87a
S25 is the grey/green at the O terminal
S27 is the red one at an L30 terminal
S32 is a black wire from B15 - the black plug again - feeds the coil and ECU

Make sure someone hasn't mixed up the black wires at B plug... Big fat one is for the starter solenoid. Thinner one is for coil & Ecu

[WidowmakerS2]

Schematics with the right colors!
Got a bridge in #8.
I'll check the B plug again, think it might be a wire missing.

[S2central.net]

Check as well that you get 12V on terminal F50Z in the 'start' key position on that black/red wire on track #2

On URs (dunno about pre S2 B3 motors) you get the starter solenoid on E50A instead of B50A but it shouldn't matter as the two pins should be bridged internally on the CEP.