Q: voltage warning light still coming on 30-45 seconds after car starts.

asked by on April 11, 2017

First problem was engine warning light came on for a few days, then it went off and voltage warning light came on. As I would drive the voltage light would turn off, and when i stopped it would come on again. Once I had replaced the alternator and battery the car would run for a bit, then driving home the voltage warning light would come on, a couple of minutes later ALL gauges and power would stop working but it still ran. When I would come to a stop the car would sputter and die. I jumped it 4 times to get me 20 miles home. Checked all fuses, traced wires, saw nothing except the positive cable was corroded at terminal end, so I spliced the positive cable today, car is now giving me an engine warning light along with the voltage warning. Next step replace positive battery cable? If it doesnt work, then replace the negative cable and ground? I can't get this thing to work! so if those don't work whats next.........Out to the desert with some dynamite?

My car has 98000 miles.
My car has a manual transmission.

Nothing should be replaced until you have in hand a definitive diagnostic pinpointing the faulty segment of the car’s electrical system. There may be too much voltage drop in the charging circuit, as well as elsewhere, but start with the charging circuit. The faulty segment could be anywhere, so using the factory wiring diagram you just have to methodically and systematically test the entire charging circuit until the fault is found. It’s laborious but compared to replacing parts that might be perfectly good, properly diagnosing the fault will save you money and time in the end. As far as the engine warning light, at the moment I would fix the issue with the charging system first because that may resolve the check engine light. If it doesn’t, just request a check engine light diagnostic. If you want the charging circuit diagnostic steps performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a charging circuit diagnostic and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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