Mystery electrical problems are always a hassle, but when your customer’s car is dying in the rain it can be a real problem. This is what one technician and SureTrack community member experienced when their customer came in with a 2004 Jaguar XJ8 4.2L, complaining that the engine would die when the wipers were turned on. Let’s take a look at how the tech solved this conundrum.
Diagnosis
Going into the fix, the tech found that the vehicle was running rough intermittently and had lean codes. The weird thing was that the ABS/track light comes on and off, the wipers creep up on their own from the park position and when the wipers were turned on the engine dies.
After understanding the symptoms, the tech referenced the service bulletin and checked the grounds of the battery area and wiper motor. He also took the liberty of repairing a vacuum leak in the PCV system and replaced the third ignition coil that was misfiring. After this, all three problems were still present, but the biggest issue was the engine dying when the wipers were turned on, understandably. Looking at the wiring diagrams, he couldn’t see anything in common with the three systems. Frustrated the engine would not even run with the wiper motor unplugged, the technician turned to a fellow community member. The technician recommended checking the ground wire behind the passenger headlight to make sure it is okay and load test the circuit.
Fix
After taking the fellow SureTrack community member’s suggestion, the technician found that the ground at the back of the passenger side headlamp was actually loose and the stud had broken off with very little torque. He repaired the ground, and another happy customer is safe during this winter season.
Real Fixes from Mitchell 1’s SureTrack® expert information resource are documented issues from actual shop repair orders and community discussions. Read the Real Fix in the Mitchell 1 ShopConnection Blog.
