Alternator issue or something else
Thread Starter
Racer
Joined: Aug 2002
Posts: 396
Likes: 1
From: East Hampton CT
Alternator issue or something else
Wanted to get some feedback on an electrical issue. My '99 FRC doesn't get driven much and was due for emissions. The tech failed it due to sensors not ready. Makes sense since the battery was disconnected. Hooked in my OBDII reader and went for a couple of rides to go thru the drive cycles. Couple of times the engine simply died but would restart no problem. But all the sensors would reset to not ready. Doing the required searches lead me to believe either a bad battery or bad grounds. Cleaned up all the grounds and tried going on more rides to complete the drive cycles. Again the the engine dies but restarts.
Took it to NAPA for them to load test the battery. He runs through the process (e.g. blower on max, headlights turned on with highbeam, revving the engine, etc) and he notes the alternator drops to 6V from time to time. I'm a little surprised to hear that since a charge fault code was never thrown.
Has anyone else had a similar issue?
Took it to NAPA for them to load test the battery. He runs through the process (e.g. blower on max, headlights turned on with highbeam, revving the engine, etc) and he notes the alternator drops to 6V from time to time. I'm a little surprised to hear that since a charge fault code was never thrown.
Has anyone else had a similar issue?
Race Director
Joined: Apr 2007
Posts: 11,150
Likes: 890
From: South Western Ontario
It's next to impossible for the alternator output to drop to be randomly dropping to 6V without the battery being completely dead.
Sounds like a bad connection.to me. I would check the connections at the starter solenoid.
Sounds like a bad connection.to me. I would check the connections at the starter solenoid.
Racer
Joined: Sep 2019
Posts: 427
Likes: 121
If you have an advanced auto parts store near you, give them a call and ask if they Midtronics tester. Free Test, It will test the battery and starter and alternator all in one test. They will give you a print out at the end.
Racer
Joined: Sep 2016
Posts: 279
Likes: 77
From: Granby CT
I'd agree with lionelhutz, an alternator doesn't just drop voltage like that. and if your battery was shot it would struggle to restart the car. my assumption would be a bad connection or a bad ground. I also doubt that its the connection at the starter solenoid. a starter would produce voltage even if that would completely disconnected. Id expect the issue to be with the 3 pin harness connected to the alternator. These are the generator on off signal, field duty cycle and battery positive voltage reference. id ensure that this harness i connected well and in good shape. Electrical bugs suck, I feel your pain HeadsUp. Good Luck
