P38 1995 Diesel in tank pump plug wire identification

Hello folks
please can anyone identify the 4 wires of the fuel tank pump plug, i want to test if i have power to the pump as i have no fuel to the under bonnet filter housing and cant hear the pump running. regards Gary

With a 95 the pump will only come on with engine running and glows on or if you have a hot start fitted you can cycle ignition.
To test You should power it direct by jumping the relay

RangeRoller dt said:

With a 95 the pump will only come on when cranking and glows on or if you have a hot start fitted you can cycle ignition.
To test You should power it direct by jumping the relay

Click to expand...

RangeRoller dt said:

With a 95 the pump will only come on when cranking and glows on or if you have a hot start fitted you can cycle ignition.
To test You should power it direct by jumping the relay

Click to expand...

Thanks for the reply, is there a circuit diagram on those relays to identify the pins .

Gary East-Yorks said:

Thanks for the reply, is there a circuit diagram on those relays to identify the pins .

Click to expand...

All the diagrams are on RAVE.

RangeRoller dt said:

With a 95 the pump will only come on when cranking and glows on or if you have a hot start fitted you can cycle ignition.
To test You should power it direct by jumping the relay

Click to expand...

Surely the 95 only runs the pump when cranking and the glow plugs are on, the third option was added on later models. It also runs of course when the engine is running.

Datatek said:

Surely the 95 only runs the pump when cranking and the glow plugs are on, the third option was added on later models. It also runs of course when the engine is running.

Click to expand...

Yes that is what is said. They fixed it on the later models, this is why they fit a hot start mod to the earlies like ‘95. With the mod the glows and pump will run every time you switch the ignition on.

RangeRoller dt said:

Yes that is what is said. They fixed it on the later models, this is why they fit a hot start mod to the earlies like ‘95. With the mod the glows and pump will run every time you switch the ignition on.

Click to expand...

@RangeRoller dt Right, my memory is not so good these days.
On early cars the pump only runs with the glow plugs on or the engine running. Diode D4 was added on later cars to run the pump whilst cranking in an effort to overcome hot starting problems.
The hot start fix causes the pump to run on a hot engine by bringing the glowplugs on.

I see what you mean I’ve typed it wrong

‘95 is engine running and glows.
Pump only runs while cranking on later models