Elictrical Problem

[Dame]

Hello everyone, its been sometime since I posted on this forum! Unfortunately it's not to answer someone else’s question but to ask for some help.

Yesterday evening, when I was driving home from work, the red engine light, CAT light and Battery light started flickering intermittently (all on at the same time).

Now this morning it started happening again. When sitting at idle, the car was fluctuating + - 250 rpm.

In terms of performance the car seems fine, and the ECU hasn't picked up any faults. The lights flicker consistently when I turn on the ignition before starting the car and fairly frequently during driving. Taking into it happens before the engine has started, I have ruled out:

Faulty alternator - since the engine would have to be running in order for the regulator to be providing power.

Faulty coil - again the engine would need to be running.

It all happened after some heavy rain yesterday, so I'm pretty sure that it could be water in some of the wires or of course our old friend the dodgy earth. I was wondering if anyone else has had the same experience as me, and whether they can offer any advice as to where to look. I'll have a long weekend ahead going through the whole car otherwise!!

Thanks in advance,

Damien.

[System~G]

Pop it in to your local Halfords and get a free Battery test done. Make sure they also check the altenator is working.

If all checks out OK, then start looking at other faults (like a possible bad earth, moiuture etc...)

[Bobby-H]

Hello everyone, its been sometime since I posted on this forum! Unfortunately it's not to answer someone else’s question but to ask for some help.

Yesterday evening, when I was driving home from work, the red engine light, CAT light and battery light started flickering intermittently (all on at the same time).

Now this morning it started happening again. When sitting at idle, the car was fluctuating + - 250 rpm.

In terms of performance the car seems fine, and the ECU hasn't picked up any faults. The lights flicker consistently when I turn on the ignition before starting the car and fairly frequently during driving. Taking into it happens before the engine has started, I have ruled out:

Faulty alternator - since the engine would have to be running in order for the regulator to be providing power.

Faulty coil - again the engine would need to be running.

It all happened after some heavy rain yesterday, so I'm pretty sure that it could be water in some of the wires or of course our old friend the dodgy earth. I was wondering if anyone else has had the same experience as me, and whether they can offer any advice as to where to look. I'll have a long weekend ahead going through the whole car otherwise!!

Thanks in advance,

Damien.

←

Sounds like a loose connection/dodgy earth to me.

[boundsw]

I had a similar problem.

all my dash lights cam on, battry, abs, etc....

turned out to be loose connected Battery, went over a bump, dislodged it, then that was it when i switched off the car, it wouldnt start.

re-tightened the Battery - ok

sounds like a loose conenction some where

but yeah, you coil and alternater should be fine of the car would not run !!

[Dame]

Well as I knida guessed it isn't a problem with Battery or alternator. The engine is now idling at 500 rpm, I did try resetting the ECU, but as expected didn't help. Battery teminals are nice and secure too.

The strange thing is that when I power up the Air Con, rather than stalling, the car revs up as normal and correctly compensates for the incresed load.

I'm wondering is there is something wrong with the idle speed sensor or something like that - I'll have to delve into the workshop manuals tonight. Strangely, so far, the car still performs as normal. There is no evidence of misfiring etc. and accelleration is smooth. I'm just hoping that it doesn't conk out in the M4 roadworks tonight, though running with the Air Con on keeps the revs up. A strange temporary fix, but one that will have to do for now.

Does anyone know where the main earthing points are for the electrical system?

P.S Thanks for all the feedback so far, much appreciated :)

[Dame]

All sorted, after investigation I discovered that these are two unrelated problems. Engine is now running fine again - turned out to be a split in the one of the pipes leading to the charcoal canister. I still have the electrical problem, but it doesn't seem to affect anything, so I'll give it a look over this weekend, more than likely to be a loose connection or dodgy earth. As long as the engine runs smoothly, that's good enough for me!!