I’m plastering the web looking for ideas and pointers as I prepare to investigate my car’s electrical issues. If you have any theories, please, post them! So here’s the story…
On Friday, I decided to move my old 300zx out of the garage so I could do some cleaning. I haven’t driven it in a week, since it’s been snowing and icing and freezing for the last few days. I turn the key…and nothing happens. Not a single click. The sound of silence. I notice that the headlight switch is turned on…must have drained the battery…
So, I proceed to jump it. Connect the cables in the right order with both cars off, turn on my “electricity donor”, get in my “recipient”, turn the key and…I see a small amount of smoke come from near, or under, the battery. I also heard the power antenna motor engage when the key was in the accessory position (didn’t raise it like normal, the stereo didn’t turn on either…maybe just enough voltage to engage the motor, but not enough to engage anything else?), but no dash lights, no cranking, no other signs of life. Turn off the car, disconnect everything, investigate. I didn’t find any evidence of burnt wires or other damage. First instinct was that I mixed up the cables, but I verified that they were +/+ and -/- while disconnecting. To be honest, I then thought it was corrosion on the battery terminal and jaws burning up.
I still wanted to charge the battery, so I disconnected the negative terminal from it, and charged the battery up with my other car for 15 mins. No smoke from the battery. To see if any life could be seen, I then reconnected the negative terminal, got in, turned the key…and smelled electrical burning. Again, the ONLY thing that engaged was the power antenna motor. No lights, no cranking. Of course, I disconnected the battery again, and began tracking down the source of the smoke. Traced it to the main bundle of wires on the passenger side foot well, below the battery and behind the ECU.
I haven’t traced it any further or started pulling out the ECU and wiring bundles. I also haven’t had a chance to check all the fuses and fusable links yet…please forgive me, it’s been -5F out since this happened, and I don’t have a heated garage!
So, has anyone ever seen symptoms like this? No signs of life at all before jumping. None after, EXCEPT for a motor on the accessory bus…and smoke coming under the passenger dash. Smoke started when jumping car and continued UNTIL battery was disconnected.
My plan of attack:
-Is the battery good?
-Check fuses and fusable links
-Check battery cables and ground links
-Remove and test ECU
-Check cables and connections behind ECU/footwell area- my best bet it that a 30 year old connection shorted out
-Check stereo wiring- I recently installed a new head unit and speakers…maybe I screwed something up. Strange that it would work for a month though
Any ideas? I’ll post here with updates…electrical work isn’t my forte, so I may need pointers if you can offer them! I’m also concerned about damage to other electrical components of the car.