Things not working after garage "fixed" the pump

[madbilly]

Hi everyone,

After I finally got my car back from the garage (long story, see elsewhere) which had got the fuel pump working by bypassing the immobiliser, I found that the fuel gauge doesn't work and the fuel pump doesn't stop priming when the ignition is turned on. I wonder if they just didn't put things back together properly after their investigation so I need to work out where the loose connections are. It could be that it's not actually the garage in the UK that didn't put things back together, it could have been the garage in France that originally investigated.

I checked the electrical diagrams and think I worked out that the gauge simply needs reconnecting and the fuel pump priming may mean that the ECU needs reconnecting to the fuel pump relay contactor as it needs feedback of the relay state before the two second countdown starts, OR the ECU thinks the engine is running which means that a connection from the ignition module is shorted to 12V - seems unlikely, but possible I suppose. But where are these connections?

I assume that the fuel gauge sender connection is on top of the tank? And the other end is behind the instrument console (probably not easy to access).

The fuel pump relay is next to the battery so I hope the connection to the ECU is also there? And at the ECU end on the big connector to the ECU?

The ignition module to ECU connections I presume are either at the coil pack or ECU ends. I suppose this could also mean that the CAS is not connected properly but this would generate a fault code and there isn't one. I imagine that an ECU to coil pack loose connection would also trigger a fault code,, so I presume therefore that the real problem is a loose connection from the relay to the ECU.

Cheers

[Simon_P]

The fuel pump is controlled by the ECU if the engine
Isn't running after 2 seconds it switches it off.

It sounds like they have comnected it to an ignition switched supply rather than the one from the ECU. The detail is in the EMJ / EMK manual.
Yes, the comnections will be at the ECU and the pump relay but I'll guess that the two are not connected as it would work if they were.

Yes gauge sender connection on top of tank - sounds like they forgot to recconect it.

Too many unconnected presumptions, suppositions, and imagines in your last para - not sure what the problem is

[madbilly]

Hi Simon,

I think you're right, the garage probably bypassed the ECU completely which is quite irritating. I hope they didn't mistake the ECU to be the immobiliser, because that would mean the ECU is starting to become faulty. More likely they just bypassed the immobiliser and the ECU, in which case I need to undo their work and just bypass the immobiliser.

My last paragraph was thinking out loud about how the ECU knows the engine is running because this how the ECU controls turning of the fuel pump. However I think that if the ECU thought the engine was not running then there would be a fault code at least.

Cheers

[Simon_P]

Oh I see, I thought you had another issue. Yes, the ECU knows if the engine is cranking or running. I think from the CAS pulse.

I'll guess that the fuel pump /immobiliser wire will be a pain to find.