Battery Draw Test ??
Thread Starter
Instructor
Joined: Feb 2014
Posts: 135
Likes: 5
From: South Jersey
Battery Draw Test ??
Ok so now I figured I better do a draw test, put my multimeter in series on the battery and with everything off when I touch the terminal the headlamp motors (both) start to turn and the meter reading is extremely high ( 700-800 ma) and fluctuates. as soon as the headlamp motors stop ( about 4 seconds) then the reading drops to 0. So any thoughts from any one would be very appreciative. I got to get this straightened out -its cruising time and I cant be carrying a jump box in a Vette. ewwwwww
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
If you have the meter hooked up properly the reading should never drop to zero, there should always be a reading somewhere around 25ma, to a maximum of 50ma .. Try unpluging the headlights and then taking a reading to see what you get...If the headlights are flipping over without you pulling the headlight **** then I would say that could very well be your parasitic drain..Im not an electical expert like a few of the guys on here, but it may be a bad headlight switch or a short in the wires...Hopefully the electrical guys will chime in....
.. WW
.. WW
Last edited by WW7; May 6, 2014 at 09:44 AM.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Might be a relay sticking open that causes the motors to run when they should have stopped. The headlamp switch would be another possible culprit.
You really need to get a Factory Service Manual set for your year of C4. The '92 FSM is a two book set. The second book has complete wiring diagrams for each component and a step-by-step troubleshooting procedure. Pics of the locations of relays, fuses, harness connectors are all there. The wiring diagrams also show the ground wiring circuits and where the grounds connect to the frame.
The C4 Parts For Sale section would be a good place to start searching for a '92 FSM. Make sure the books have red covers.
You really need to get a Factory Service Manual set for your year of C4. The '92 FSM is a two book set. The second book has complete wiring diagrams for each component and a step-by-step troubleshooting procedure. Pics of the locations of relays, fuses, harness connectors are all there. The wiring diagrams also show the ground wiring circuits and where the grounds connect to the frame.
The C4 Parts For Sale section would be a good place to start searching for a '92 FSM. Make sure the books have red covers.
Race Director
Joined: Aug 2007
Posts: 11,889
Likes: 8
From: Whitefish Falls Ontario
St. Jude Donor '08-'09
If you have the meter hooked up properly the reading should never drop to zero, there should always be a reading somewhere around 25ma, to a maximum of 50ma .. Try unpluging the headlights and then taking a reading to see what you get...If the headlights are flipping over without you pulling the headlight **** then I would say that could very well be your parasitic drain..Im not an electical expert like a few of the guys on here, but it may be a bad headlight switch or a short in the wires...Hopefully the electrical guys will chime in...... WW
.. WW
4 seconds is roughly the amount of time it would take to do a complete cycle open or close.. How does the motor work if you put the headlights on and off? Do you get the extra run on when it is open and then when its closed? If you have the same run on or jerky operation, might be time for new pellets..
Might be a relay sticking open that causes the motors to run when they should have stopped. The headlamp switch would be another possible culprit.
You really need to get a Factory Service Manual set for your year of C4. The '92 FSM is a two book set. The second book has complete wiring diagrams for each component and a step-by-step troubleshooting procedure. Pics of the locations of relays, fuses, harness connectors are all there. The wiring diagrams also show the ground wiring circuits and where the grounds connect to the frame.
The C4 Parts For Sale section would be a good place to start searching for a '92 FSM. Make sure the books have red covers.
You really need to get a Factory Service Manual set for your year of C4. The '92 FSM is a two book set. The second book has complete wiring diagrams for each component and a step-by-step troubleshooting procedure. Pics of the locations of relays, fuses, harness connectors are all there. The wiring diagrams also show the ground wiring circuits and where the grounds connect to the frame.
The C4 Parts For Sale section would be a good place to start searching for a '92 FSM. Make sure the books have red covers.
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Thread Starter
Instructor
Joined: Feb 2014
Posts: 135
Likes: 5
From: South Jersey
I rechecked it, I get 3.1 amp when I first touch terminals then after the motors stop turning (headlamps do not go on and doors don't open) then it drops to .16 amps. I'm thinking I believe theres a relay and maybe its bad. The headlamp motors I believe always turn when I would turn on the key
Race Director
Joined: Aug 2007
Posts: 11,889
Likes: 8
From: Whitefish Falls Ontario
St. Jude Donor '08-'09
As stated by WW7 the maximum draw s/b no more than 50 ma or .05 amps. As I stated above if you have a 92, there are no relays for the doors but a module, see drawing.. You need to start pulling fuses until you find the circuit with the draw, make sure the under hood lights are unplugged and any open door switches are blocked closed..
Did you try operating the headlight doors with the switch?
Did you try operating the headlight doors with the switch?
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Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
Also when checking for a drain, you have to wait for the interior lights to time out, this usually takes a minite before you can get an accurate reading... I always use a jumper wire from the battery to the cable so I don't lose all the information, radio, clock, etc, and so the ecm doesn't have to relearn everything.....WW
Le Mans Master
Joined: Feb 2000
Posts: 9,061
Likes: 214
From: Epping NH
I rechecked it, I get 3.1 amp when I first touch terminals then after the motors stop turning (headlamps do not go on and doors don't open) then it drops to .16 amps. I'm thinking I believe theres a relay and maybe its bad. The headlamp motors I believe always turn when I would turn on the key