fuel pump

[Chimp871]

gremlins time.

New alarm/immobiliser from abacus installed.

Ignition on, both relays click, no pump prime but engine cranks over. Check pump +ve wire volts at B pillar behind passenger seat and at cranking it's ~10v, stop cranking it goes to ~12v before pump relay switches it off (normal) - pump does not prime.

Stick direct 12v feed to pump and it primes. Car starts. Switch engine off and try as normal and of course if works, several times.

Are these typical signs of a pump being knacked (no weird noises at the moment), just wondering if these things can jam and bar a technical tap or a good battery boost, gets them going again.

[Chimp871]

Probe kit: 12v direct to +ve on pump with negative connector on chassis where suppressor is.

So I've a voltage drop between pump relay and connector in B pillar. How many connectors are there upto the pillar?

Alarm (black plug under dash)
Intertia

Anything else? I'll check for resistance between points.

Blitz - can't measure pulse..

Edited by Chimp871 on Monday 17th September 13:02

[Chimp871]

Update : so checked Volts between fuel pump +ve in B pillar connector and battery - ve and its gone from 10 to 12v and of course working fine.

Same question as above, what connectors are there between b pillar and relay?

[Chimp871]

SwanJack said:

http://www.bertram-hill.com/fuel-pump-schematic.ht...

There you go

Thnx for that. So the plug with just black wires is near the alarm and goes off to the immobiliser but the other one, to right of picture with brown/blue socket is where?

[Chimp871]

found the brown connector, it was hidden well. It is in the stereo slot but behind a flap that you can only see if you look through the passenger 'glovebox' sideways. Sprayed contact cleaner and checked connections, nothing obvious. Working now, fingers crossed.

[Chimp871]

Yes pulled apart and nothing obvious. It's going to be a case of if it repeats then I can check the connector. Been looking a while for it

Meanwhile, my o/s wheel bearing went today so the gremlins have been busy, little bds!