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Bosch Alternator problem

Hi all

I have a 2003 Seat Ibiza TDI Sport, with the VW TDI PD130 engine, on

63k miles. As far as I can tell, it's fitted with a Bosch 90A alternator.

Recently I've started getting a warning light illuminating from time to time. I hooked up vag-com and I keep getting the following fault:

17911 - Load signal from Alternator Term. DF: Implausible signal

Typically on my 40-odd mile commute, it will happen 3 or 4 times - each time, I restart the car and the light goes out for a while. The fault does not seem to coincide with any particular driving style or movement, and can come on at any engine speed.

The voltmeter on the dash always shows a healthy 14v, and there are no other noticeable faults. The connections to the alternator all look fine - 1 main charge cable, and two small wires sharing one connector.

My knowledge of alternators isn't great - can anyone suggest what the fault might be ?

The car is out of warranty, so I'm loathe to pay the stealers prices to fix it.

Any ideas ?

Thanks!

Reply to
muddyboots
Loading thread data ...

Dirty connecter to the back of the alternator.

Reply to
Duncanwood

The charge cable is secure. I removed the 2-way connector to check it, this was perfectly clean and secure too...

Reply to
muddyboots

I've not gor it for that model but the erwin electrical systems troubleshooting sheet night be your best chance, also the vag-com forums & US Audi forums.

Reply to
Duncanwood

Thanks for your reply.

I hadn't heard of erWin until I just googled for it; any idea how much it costs to get hold of such sheets ? (Unfortunately the search only lists Ibizas up to Mk3, mine is a Mk4...)

If one was to find it's way to me I'd be eternally grateful ;)

Reply to
muddyboots

More than likely a faulty regulator on the alternator. Modern alternators have an additional data connection to feed load info to the ECU. Everything will work away ok if you can put up with the light flashing on and off. Otherwise fit a new regulator.

John.

Reply to
John

Thanks John... Worked out today that the warning always illuminates exactly 10 minutes after the engine is started...so I guess the ECU tries reading an erratic signal for 10 minutes before deciding to give up and flag a fault.

I don't think regulators cost that much, so no harm in trying one.

Cheers Lee

Reply to
muddyboots

I've Googled for erwin electrical systems troubleshooting sheet and drawn a blank. Do you have a link please.

Thanks

Reply to
Alt Beer

formatting link

:)

Reply to
muddyboots

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