Audi engine, ABS and traction control lights
When the dash lights up with an ABS and traction control (TC) soon after you have just spent the past week diagnosing and rectifying another fault in the engine bay, you think, “When is it going to end?” A simple precheck of the entire operating system is all it takes to prevent something like this happening. How many times have we heard this quote? “Ever since you...” I’ve given that customer a name: “Eva Sinsu.”
We had a member’s case where a 2009 AUDI Q7 (4L) CASA engine 3.0L TDI with 177k on the clock arrived at the workshop with a complaint of low power and the engine light on. The scan tool was plugged in, and the technician went directly to automatic search for the vehicle – my pet hate. It might sound like a longer road but trust me, diagnostics must never be rushed. I prefer to take my time and ensure I have selected the correct vehicle system and scan each individual control system plus I check the OBD section for any hidden extras. Sure, the automatic system does this, but how many stop to look at Body Control Modules (BCM) when they’re diagnosing an engine fault?
During the scan the historic ABS code was overlooked, and the technician intake swirl actuator motor failure. The plastic actuator arm becomes worn and wears away the internal bush eventually internal position sensor to fault. I’ll come back the ABS and TC lights later in this article.
This fault would cause a loss of performance which is often a result of the engine light appearing and a code registered causing the engine to derate. Most of our members are aware that there is only one diagnostic scan tool worth plugging into an Audi and that is the Ross-tech VCDS. The VAG (VW and comes with an interface to be coupled with a suitable computer. VCDS Ross Tech is available from Mount Auto Equipment. www.autoequipment.com.au/scantools-and-accessories/vcds
Ross Tech VCDS Pro Kit.
sensor bank 2 implausible signal and on other scan tools a P2020 – Inlet manifold what we refer to using Hayne Pro workshop data. fault: There are a couple of ways to test the actuator for failure. A quick evaluation of the swirl actuator’s condition can be to simply reach for the actuator arm and give it a wriggle test. When worn, the small pivot arm with the ball joint will feel sloppy when moved side to side. To ensure you are grabbing the actuator arm, unclip the connecting arm which is a replaceable part shown in the image below that intake manifold.
there is electrical current reaching the actuator. Connect the diagnostic tool and activate the Swirl control actuator. Check the dwell readings and the position sensor parameters. If there is no correlation between the values, proceed as follows. Using the diagnostic tool, carry out an actuation test. If no movement is observed, proceed as follows. Remove the swirl control valve and check for carbon deposits.
This information was taken from Haynes Pro Smart Case on fault code P2015 – Inlet 480F – Inlet manifold runner position (bank 1).
The intake design of this V6 engine has two individual manifolds for each cylinder head. It is common for inlet manifold 2 has failed and vice versa. To avoid any rework from occurring, make sure you test your customer that both must be replaced at the same time. Bank 1 fault codes can range between P2010 and P2019 whereas bank 2 code range can be between P2020 and P2029. H5 on the imag: Haynes Pro should be ok.
Solution: The actuator is part of the manifold and therefore must be replaced as a complete intake manifold assembly. Due to the age of the vehicle, the EGR valves are often near failing and the EGR coolers are often blocked. Due to the location of the repair, it is important to quote to replace EGR coolers and EGR valves too. Replacing the intake manifolds is an expensive
exercise but must be done to ensure the reliability of the engine. Using the diagnostic tool, calibrate the sensor.
Some customers may have already researched the issue and requested the cheap alternative to the full repair – A will lead to a failure of the engine. Swirl is the integral process of the engine’s combustion. Without full swirl, the diesel engine’s life is greatly reduced. This is caused by the poor burning of the fuel and air during the combustion process. It leads to washing of the cylinder bores because of incomplete combustion.
ABS and traction lights appearing at 60 km/h
So back to these dreaded ABS and traction control (TC) lights the customer forgot to mention since becoming used to its intermittent presence. When the vehicle was faulting with the engine light and intake swirl codes, that would have to reach around 2500 rpm until it went into limp mode. The ABS and TC were appearing when the vehicle reached 60 kph. The cause of these faults is the vehicle. All Wheel Drive (AWD) systems rely on the rotational speed of each wheel between each wheel to ensure accurate operation of the safety braking and traction control system.
I came across this issue back in my short time as an OE dealer service manager resolving an automatic transmission lock up on the AWD SsangYong Rexton. We had several of then making a harsh crunching noise as soon as the car moved from the driveway. It was such a shocking sound; some customers were afraid to drive any further in fear of the transmission blowing up. It was a relied on wheel speed sensors as one of the important input signals to determine when AWD and traction should engage. If the vehicle is climbing over rough, uneven terrain, it’s going to have varying wheel speeds at times.
The popular culprit was the customers ignoring to replace all four tyres at the same time when one or two would wear from out of alignment scrubbing. Often full set at the same time but unfortunately were unaware of why or how to sell it. A simple short low speed drive whilst recording each wheel speed sensor, would other 40mm. I’ve witness exactly same printed on the tyre.
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