1991 525i fuel pump voltage problems

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

John J - 02 Mar 2008 18:22 GMT

I have a 1991 525i that has no voltage at the fuse for the fuel pump. I have
changed the relay for the fuel pump already, can someone tell me where to
check next?

Reply to this Message

hsg@h-gee.co.uk - 02 Mar 2008 21:44 GMT

>I have a 1991 525i that has no voltage at the fuse for the fuel pump. I have
>changed the relay for the fuel pump already, can someone tell me where to
>check next?

The ECU controls the pump and it also connected via the speed limiter which in
your case is not needed as the car won't touch 155mph but it is still controlled
by the ECU - perhaps it gone dead.

Signature

Sir Hugh of Bognor

The difference between men and boys is the price of their toys.

Intelligence is not knowing the answer but knowing where and how to find it!

Hugh Gundersen
hsg@h-gee.co.uk
Bognor Regis, W.Sussex, England, UK

Reply to this Message

Scott Dorsey - 03 Mar 2008 01:24 GMT

>I have a 1991 525i that has no voltage at the fuse for the fuel pump. I have
>changed the relay for the fuel pump already, can someone tell me where to
>check next?

Okay, as I recall, the fuel pump is powered by the fuel pump relay, which
is powered by the main relay. Main relay has power at all times, which
it gets through a fusible link right off the battery, right?

The electrical manual will tell you for sure, and barring that you can take
the fuse box apart and see where the wires go. You sure the main relay is
good? Put the relay you took out of the fuel pump position into the main
relay spot.
--scott

Signature

"C'est un Nagra. C'est suisse, et tres, tres precis."

Reply to this Message

John J - 18 Mar 2008 08:02 GMT

That was it, I swithced the relays around. There were three of the same
type. Thanks a lot.

>>I have a 1991 525i that has no voltage at the fuse for the fuel pump. I
>>have
[quoted text clipped - 11 lines]
> relay spot.
> --scott

Reply to this Message

Scott Dorsey - 18 Mar 2008 16:10 GMT

>That was it, I swithced the relays around. There were three of the same
>type. Thanks a lot.

My local dealer insists that the Bosch relays "never fail" and that if
there is some electrical problem the relay is the last thing to check.

He's wrong. And there are a _lot_ of relays that all need to be working
right.
--scott

Signature

"C'est un Nagra. C'est suisse, et tres, tres precis."

Reply to this Message

Rate this thread: