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Matt
Matt, Mechanical Engineer
Category: Audi
Satisfied Customers: 21619
Experience:  BEng hons Mech engineering, in auto industry 22 years
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My car wont start. ESP fault

Customer Question

My car won't start. ESP fault
Submitted: 3 years ago.
Category: Audi
Expert:  Matt replied 3 years ago.
Hello

ESP faults with no start means that there could be a problem with the power supply to the ECU or a issue with the ABS / traction control system that shutting the engine down prematurely

ideally the most cost effective way forward is to have the car plugged into a VAGCOM system tool which can pull up the fault codes and point to the fault directly - yes there will be a diagnostic charge but you'll save time and money with this method

its also worth checking that you have 12V present at the ECU fuses in the fusebox under the dash and that the ECU power relay is clicking in when you turn the ignition on

another possibilty is an issue with one of the wheel speed sensors and I'd first check the connections at all four corners first for any signs of corrosion or chafed wiring.
The sensor is located in the wheel hub so you'll have to remove each wheel in turn to inspect them all.
Also check that the toothed wheel that the sensor points to is clean and free of any debris.
you can check each sensor's function by plugging the two output wires into an AC voltmeter and spinning the wheel quite quickly, you should get a voltage signal that increases with rev's.

Its possible that the fault is only a bad connection to one of the wheel sensors.
This may be remedied by removing each wheel in turn and unplugging each sensor and cleaning the contacts with a squirt of electrical contact cleaner. Then refitting.

Matt and other Audi Specialists are ready to help you
Customer: replied 3 years ago.
Thanks for this info. The 12v seems to be working and clicks when the ignition is turned on. The engine partly turns over but then does not fire. I've called the RAC now !
Expert:  Matt replied 3 years ago.
Hello

OK ask about having the codes read off and let me know what they are

and I'll try to help further
Customer: replied 3 years ago.
Thanks. Will do
Expert:  Matt replied 3 years ago.
no problem
Customer: replied 3 years ago.

Flat battery !! It was seven years old ..All fixed . Thx for your help.

Expert:  Matt replied 3 years ago.
thanks for letting me know