hi guys finally down to the last fault code as i did have 7 and sorted 6.only left with po641 now i have seen were this has been down to the alternater not putting out enough output or the battery duff.now i tested my alternater and its putting out 12.74 volts that is when reved.the alternator light goes off but it should be putting out 13-14 volts.now can this defo cause p0641 to keep comeing back on and keeping the engine managmant ligh on.any one had the same problem.

Alternator output should be between 13 and 14 volts as you say.

However, P0641 = "Sensor Reference Voltage "A" Circuit". It refers to the 5 volt reference supply from the ECU to the various engine sensors being to high or too low.

Unless the alternator output voltage is going below 12 volts (perhaps under load from consumers?), I doubt the alternator is the cause of the fault code. Measure the alternator output with headlamps and heated rear window switched on.
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See if you have a 5V feed to the sensors, had a similar fault on a corsa and it was a blown fuse.

i have also had that triangle orange light come on with the escalamation mark in the middle but if i switch ignition off then restart it goes off.

smudge67999 said:

i have also had that triangle orange light come on with the escalamation mark in the middle but if i switch ignition off then restart it goes off.

Click to expand...

This means a light bulb is gone.
When you switch on, the lcd tells you which one.

hi that code po641 could the problem be because i have a sensor gone which is the map sensor just waiting for it to arrive.is this why it may not be clearing and comming back on.