B9 SQ5 Air Suspension Fault
Source: National Highway Traffic Safety Admin
The other day we washed the shop B9 SQ5 as we would any other time. Taking care to make sure all the wheels and tight spots were cleaned. It then sat for two days, which isn't uncommon as we don’t use it everyday. Two days later when we started it up we received an error on the dash saying Suspension Malfunction: You May Continue To Drive & Audi Adaptive Lighting Malfunction, along with the dreaded yellow triangle exclamation mark. Upon scanning the car the only suspension code that came up was C103415 - Front Left Ride Height Sensor. Since the B9’s with air ride have come out we have never replaced a ride height sensor. Not believing that this was the true issue we investigated what else could be causing the issue. We found an Audi TSB on the NHTSA website describing the issue we currently were experiencing. It stated that damage may have occurred to the wiring harness for the front left height sensor during production. It explained where to check for this potential damage (Figure 1). Upon getting our SQ5 in the air and taking off the protective covering, we found that one wire was completely corroded and broke in half the second we touched it. The second wire had missing sheathing and was starting to show signs of corrosion as well. It was not as bad as the first wire but sure enough this looked to be the root of our issue. It is perplexing that it took this long to show its face since the car is a 2019 with 65,000 miles on it. And we have not seen another one with this issue, even though it appears to be somewhat common. We cut the damaged sections out and used weatherproof butt connectors to reattach the wires. Before we heat shrunk them we plugged in the height sensor and turned on the car. Sure enough the dash warning was immediately gone and the fault cleared out. We then heat shrunk the connectors, tapped up the wiring to protect it from water and reinstall everything back the way it was from the factory. Although this is an uncommon issue, this could have easily been misdiagnosed. If time was not taken to look into the issue and instead just based the repair off the scan tool, it would have been costly. One height sensor from Audi is $313.34, and that doesn't include labor to install! Instead we repaired the wiring damage, which if this was a customer's car would have cost them less than $155.00! This example shows the importance of thinking a little outside the box and not just replacing the first thing the scanner says has a fault. See the repair below.
The finished repair (green clip and wiring).
Check back weekly for more shop updates!