Cadillac Repair Questions? Ask a Mechanic for Answers ASAP
Hello, my name is Bobby. Thanks for the question. This is almost always caused by a voltage issue. If the voltage is low enough in the system this will occur. I would start by testing the battery and the alternator. If those are both fine then some of the time this is an ignition switch problem, but the majority of the time it is a battery cable issue. This vehicle has a ton of issues with the battery cables failing internally and causing this. You may want to replace those if everything else tests fine. Did you plan on fixing this yourself?
Thank you. You can have the battery and alternator load tested by most auto parts stores for free. I would pay attention to what you mentioned though. I would clean all grounds and make sure that they are tight. I have had more positive battery cable failures on this vehicle than anything else that I have worked on. Unfortunately it is very hard to diagnose. One other place to check, since this happened after the wash, is under the kick panel under the far left side of the dash. I have found water intrusion in that area that can get into connections and cause this.
The positive cables has one lead that goes to the buss bar above the battery and the other goes to the starter. As for the ground, you have the one that goes to the front of the engine and the one I have seen the majority of the problems with is the one that goes to the front of the passenger side frame.
The grounds I mentioned are just for the cable. There are other grounds but these will not typically cause this. As for the positive, it is not the section that goes to the starter that usually causes this. It is typically where the connection end connects to the cable or right after and it has a voltage drop in the cable itself.
Unfortunately I am in California. As for the grounds that your dad mentioned, there are issues with it that will cause various issues, but not typically what is occurring with your vehicle. As for the air bag light this is typically caused by either a failing seat occupant sensor or the wiring under the seat. I would recommend checking the wiring under the passenger seat to see if any of the wiring is worn through from the seat moving. If any of it is worn then it can definitely cause a series of electrical issues.
Unfortunately unless it is a recall it will not be covered for free. Are the symptoms still there every time you drive it?
Most of the time it is intermittent because of the voltage issue. Can you tell me what the voltage reading is at the buss bar connection and the connection at the fuse box under the hood?
With the black lead on the negative see what the voltage reading is with the positive lead at the Buss Bar and at the large metal terminal at the fuse box under the hood. See what the readings are when the key is on and when the engine is running.
Same to you. I will look for your response tomorrow.
Thank you. And was the issue occurring while testing it?
Do me a favor and check the wiring and ground connection under the passenger side front seat. Check for any broken wiring or loose connections.
No problem. I will await your reply.