Fuel pump not working

[crossie]

Can the ignition switch not working cause the fuel pump not to work?

I have had to bypass the ignition switch direct to starter to get my car to turn over
but I am getting nothing from the fuel pumps

Any one have a wiring diagram for the fuel pump wiring?

[crossie]

Conversion so power is direct (s50)
Direct to fuse box and direct to S50 loom

[DanThe]

The loom should only become fully powered up with ignition on, regardless of engine.
Pin 7 of the C101 needs to be live before anything will happen

[crossie]

the ignition switch works but has never started the car

so was bypassed to the starter

[crossie]

Dan you did my conversion loom a few years ago and the car has ran fine
But the car never started or had power to the fuel pumps.
So I ran an extra loom for the pumps and an extra wire from the ignition to the starter to get it going

Am now trying to remove my wiring and get the standard loom working correctly so everything starts on the key!

[Brianmoooore]

Possibly an old alarm/immobiliser still in circuit, connected to starter and pump circuits?

[crossie]

Wiring is totally stripped (owner before)no alarms radio wiring or any extras!

[Brianmoooore]

Wiring is totally stripped (owner before)no alarms radio wiring or any extras!

Mmmmm, sounds like a car I wouldn't have touched with a barge pole!
Fuel pump wiring is extremely simple - a single wire goes from the pump relay on the engine loom, through the C101 to fuse 11 in the fusebox, and then as a green/purple wire back along the LH sill to a plug and socket under the rear seat squab, and from there, the short distance under the floorpan to the pump. Earth connection for the pump also goes through the plug and socket to an earthing point at the LH side of the seat base.
Starter circuit is similarly a single black wire from the ignition switch, which becomes black/yellow at the switch's plug, runs along behind the dash, through a plug/socket for the starter inhibitor on auto. cars, and then up to the C101.

[DanThe]

Ive seen a few E30's with a bad ignition switch that won't power the starter so that could be the starter problem, as for the fuel pumps as long as the engine loom/ecu has ignition feed and the engine is turning the pumps should be running, or the fuel pump relay engaged at least

[crossie]

Are the pump wiring colours the same on M3?

anyone with a spare ignition switch then to test that?

[Brianmoooore]

The socket that the ignition switch plugs into should be clipped to the steering column about half way down. Find this, and use a short piece of wire to link across the red wire and the wire that is black one side of the connector and black/yellow the other. This should engage the starter motor.

[DanThe]

All you need is a test light really, test on the back of the switch for power, Green for ignition and Black/Yellow for starter

[DanThe]

Or as Brian just said

[Brianmoooore]

Plug and socket are a lot easier to get at than the back end of the ignition switch!

[crossie]

Right guys bit of time in the garage
Can you tell me which pin is for the ignition switch and which one for the fuel pump?

Also is the relay at the end the one for the fuel pump?

Thanks
Any way to test a relay is working??

[Brianmoooore]

Pics. not working. See the sticky at the top of the for sale forums to see how to host pics. on here.

[Brianmoooore]

Pin 7 is ignition live - this pin in the socket should become live when the ignition switch is on. Check with a 12 volt bulb of at least 5W, connected between this pin and a good body earth (bonnet rear latch bracket).

Pin 18 is starter signal - this should be live when the ignition switch is turned to the start position.

Pin 13 is the feed to the fuel pump. Applying 12 volts to this pin of the socket, direct from battery +, should make the fuel pump run.

Which relay is for the fuel pump depends on which order they have been clipped on the bulkhead in. It is the only one that has a green/purple going to it - easy to unclip the holder by pushing the little tab with a screwdriver and to check underneath.
Using a short piece of wire to link together pins 30 and 87 (marked on the relay itself) of the relay socket should make the pump run continuously (with the C101 plugged back together.)

[crossie]

THANKS

nice job for this evening!

[crossie]

@Brianmoooore Thanks for all you help!

Any idea why the starter solenoid switch is live as soon as you turn the key (even in the first position)