88 won't start

[Mike Z.]

Need a little help in diagnosing a problem with an 88. Car has no sign of battery voltage: no crank, no dash lights, no interior lights, etc. I put a multimeter on the battery with cables connected; shows below 6 volts. I thought the battery was toast, even thought I changed it out last year. Took the cables off and put the meter on the battery and it showed 12.7v. Installed the positive again after cleaning, etc. and still had 12.7v. I then installed the negative after cleaning and checked and only 6v again. I disconnected the positive and left the negative connected and back to over 12v. In summary, I have 12+ v with no cables installed or just one cable, but when both are installed, drops to about 6v.
I am thinking a short in the circuit somewhere. Has anyone encountered issues like this?

[Keith B.]

Re: 88 won't start

When you placed the cables back on did they spark? If they did you have draw somewhere

[Stephen L.]

Re: 88 won't start

To pull the voltage to 6V, you'd have a "significant" short which probably would result in "smoke".
Sounds like a battery issue.... have you tried to substitute the battery or at least jumpered to another battery?
I suggest you jumper with a known good battery; but first remove the negative cable. Then connect the jumper to the positive battery terminal and the other jumper to the disconnected negative cable. This isolates the "dead" battery. If you now have lights etc. then the battery is faulty

[Mike Z.]

Re: 88 won't start

Thanks guys; I will try both of your suggestions this weekend. Mike

[Mark E.]

Re: 88 won't start

It may be an abnormally high current draw, a bad battery, or both.

I don't recommend jumping with the existing battery installed. If the existing battery has a bad cell, it may just cause more problems.

Check current draw if you have a tester. If you don't, try completely swapping out batteries and see what happens.

[Stephen L.]

Re: 88 won't start

Mark, If you read my post I suggested that the negative cable be DISCONNECTED from the battery in question before connecting the negative jumper cable directly to the negative cable (car). This isolates the "old" battery, but supplies a connection point for the positive jumper cable....

[Paul J.]

Re: 88 won't start

Hello Mike,

Don't forget, 12 volts on a battery means very little. Volts and amps...volts and amps. do a load test on the battery. I haven't looked at your data but if you live near Raleigh NC, I'll do a load test on your battery for free. It sounds to me like a short. Unhook the cables and test the resistance. If they are good, it might be a starter Bendix or a voltage regulator. I know these are simple guesses but I just got out of my car an hour ago from a 10 hour drive from Cincinnati. When my head clears I'll see if I can give you a better answer.

Paul