Starting issue

Can you offer any advice on an issue with my 105k-mile 2011 Audi A4 2.0 TDI? A few seconds after putting the key in the ignition, the warning message ‘Stabilisation programme fault’ appears, followed by ‘Parking brake malfunction’, and the car won’t start. At first the fault was occasional, but is now happening almost every other start. My workaround is to put the key in ignition position 2 before starting and wait three seconds. After that, starting is as normal.

From my Foxwell NT414, I get the following fault codes from the ABS module: ‘00473: Control Module for Elect Park Handbrake (J540) - sporadic 013 - Check DTC memory’ and ‘01314 Engine Control Module sporadic 004 - No Signal/communication’.

Looking online, the Audi forums have several stories of Audi needlessly replacing EGR valves, ECUS and some sensors at a not inconsiderable cost. One thread suggested replacing the exhaust pressure sensor – the only problem is that last

year I had a different error and the fix for that was to replace this sensor, which is a Bosch G450 unit. Could this really be giving problems again? Is it worth getting another one to try? I’m not sure what the warranty is for the Bosch part, but my factors may take it back if proved to be faulty.

A thread on the Ross-tech forum suggests: ‘00473 - Control Module for Elect. Park/handbrake (J540): No Signal/ Communication’

Possible causes

 Wiring/connector(s) from/to Control Module for Elect. Park/handbrake (J540) faulty

 Fault(s) stored in Control Module for

Elect. Park/handbrake (J540)

Possible solutions

 Check Wiring/connector(s) from/ to Control Module for Elect. Park/ Handbrake (J540)

 Check Measuring Value Blocks (MVB)” What do you think? I’ll be giving the car its regular 12,000km service. Would it be worth cleaning the EGR/MAF?

John Durcan

Modern electrical systems are complex and highly voltagedependent. So, I'd first check the battery voltage. If the original battery is fitted, I'd certainly consider renewing it.

The stabilisation and the ABS are integrated into the vehicle’s other systems, but it is difficult to see how an exhaust pressure sensor or an exhaust gas recirculation (EGR) valve would cause the symptoms you describe.

The common denominator in the codes you have is a problem with communication or connection. For this reason, I would systematically go through the earth connections to the body and also check and clean all the control system plugs (ECU, ABS unit, etc). Even though you have no code showing, the component that may be giving trouble is the yaw sensor (G-419) – this is a link between the stability control and braking systems.

Finally, Autodata informs me that vehicles fitted with an auxiliary heater can exhibit the following symptoms: ‘Auxiliary heater inoperative, battery discharged, disturbance to CAN data bus communications, electric parking brake (EPB) not working, engine fails to start’, as well as various warning lamps being illuminated.

This is caused by an internal fault with the auxiliary heater control module. So, if your vehicle has an auxiliary heater fitted, this would certainly be worthwhile investigating.