Electrical fault

[GTi.Si 0]

I have a weird electrical fault which causes the engine to cut out on my VR6 with no warning! It seams to die and all the dash lights don't illuminate! It's a random fault but becoming more frequent, now it's undriveable, it cut out on a roundabout today and I had to have it towed. Sometimes it restarts by cycling the ignition sometimes the dash lights don't come back on but it will still crank but won't fire.

 

So far I've replaced the battery, alternator, ignition switch, indicator stalk and cleaned the battery connections. It seams like the immobiliser comes on? It has an aftermarket sigma alarm/immob, but this arms and unarms fine, I can even hear it click when the dash lights aren't on.

 

Any ideas what it could be? I was thinking a fuse able link? If it has one? Or a fuse box problem?

[seanl82 23]

Disconnect the alarm. It may or may not be the problem but it'll rule it out. Worth cleaning up all earth points though, and tilt the fuse box forward and make sure the connectors are all in properly. They should be locked in place by a plastic bar that pushes in on the right hand side of the box.

[Dox 23]

Relay 109 (hidden under the black wire) is the main ecu power relay, pop the plastic cover off and check for dry solder joints, you can resolder any suspected joints.

 

 

Edited December 24, 2014 by Dox

[CazzaVR 0]

If the above suggestions don't work, make sure the plug into the back of the clocks in firmly plugged in. Had very similar problem once and eventually found the the plug wasn't pushed in fully.

[GTi.Si 0]

I didn't think of the clocks, they have been out in the past to replace the bulbs. Pretty sure I've replaced the main power relay and I've definatly cleaned up the earth points! I'll take a look at it over the holidays.

[angus.lougheed 10]

Hi GTi.Si

I had a No Spark - No Start situation which I fixed by simply cleaning the ECU plug. I now have an intermitant speedo and dodgy dip headlights which I am convinced is down to the big loom plug in the engine bay which I am going after this weekend. I have recently done the headlight loom replacement and the lights worked fine at the time. The car was left standing for a few days over xmas and the really cold period set in and all sorts of electrical gremlins appeared. The car had 4 to 5 inches of snow and a thick buildup of ice all over it. I have seen what happened to the ECU plug. I would bet that the big loom plug is subjected to the same oxidation and its shown to happen on the wiki pages as I found when looking at how to open up the loom plug. There are pics on there with what look like spider webs in the plug and socket so ...... **** happens !

 

They are not related to anything inside the car as I have been through the interior wiring recently after doing a heater matrix replacement.