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View Full Version : unusual problem...need some advice.



gmachinz
05-11-2005, 06:59 AM
I have been working with a friend's '91 Chrysler New Yorker-yes, no this is not pt material but I thought I'd share this for a fresh perspective. Let me first say I think the ECM is cooked but here's the deal: This car will start and run fine for about 10 minutes, thgen it dies-with power shut off to the fuel pump, ignition module/coil and fuel injector wireing harness. The car will sometimes start right back up for a few minutes then die again but most of the time it just cranks and cranks and cranks. Two codes were present in the computer prior to me taking battery out to be charged. One code was an under-charging condition and the other was a code for occasional over-charging...all of which is determined by the ECM because that is where the voltage regulator is present. I checked the coil, module, crank sensor, alternator (on and off the car), starter relay, and all was okay. Now's here's the strange part. If I do a voltagetest at the two battery terminals, I get 12.22V every time. If I probe the neg. terminal and the pos. cable itself, I get a reading of 220-230mV. WTF? There is a main disconnect between the positive cable and the lead into the fuse box and when I dis-connect that and probe the lead routing to the battery still I get a 12.22V read again. I connect it back to the lead routing to the fuse box and it reads 220-230mV again. And if I just leave the two cable hooked up to the battery, the positive side gets real warm.....strange. Any ideas? -Jabin

derekf
05-12-2005, 03:40 AM
Not sure I really understand what you're getting at.. when you say you're checking between the terminals and getting 12.22v, was that with the cables disconnected - and with the main disconnect disconnected and the cables connected you're also getting 12.22v.. but with the main disconnect connected and the cables connected you're way down at 220mv-ish?

Or am I not really getting it?

zbugger
05-12-2005, 04:09 PM
Make sure the battery cables are ok. Then, with the engine running, check the voltage at both the alternator and at the battery. Then, between the two. With the battery cable getting hot like that, it sounds like a bad contact. I, uh...... Fried a cable once. That sucked. Smelled funny too, but it also looked cool for some reason..... I'm strange.

gmachinz
05-12-2005, 07:40 PM
LOL Allen-you've got some issues to sort out-like eating too many oatmeal cream pies....LOL No, Derek, the positive cable gets hot when both are connected to the battery. And if I probe the neg. battery post and the positive cable itself with both still connected to the battery, I get 220-ish mV but then if I probe the actual battery terminals themselves on the battery with the cables still hooked up, I get 12.22V. I'm wondering if the starter solenoid is grounding itself....? -Jabin

MrQuick
05-12-2005, 08:41 PM
Hey Jabby,
I've got a special tool kit for cars like that...a gallon of gas, 2 strike anywhere matches and marshmellows. LOL j/k

Disco the Alt, recheck, then starter, recheck, then main B+ lead. The bullet looking connector near the battery.
You might have a driver(s) that are hanging up. good luck

hessdawg
05-13-2005, 08:29 PM
hey
are your termonals clean??? top or side mount???have you checked the fusable links??

it sounds like there is to much resistance at the terminals or the main line. or some grounds are loose/caroaded thats why there heating up when connected.