95 Mustang V6 electrical problem

[Falcongunner]

My son's 95 Mustang 3.8 Auto crapped out on him after cleaning the battery cables. Keeps blowing the EEC 20amp maxi fuse. After some questioning he did tell me that while removing the positive cable with a adjustable wrench that he hit the body a few times and sparked. This fuse controls the powertrain control module and the constant control relay module. It starts and runs a few seconds and then blows the fuse. Any thoughts on what is fried?

Wayne in FW

[Falcongunner]

Bump

[Falcongunner]

Still looking for answers to this problem. If I rig up a jumper where the fuse goes and wait until something smokes will I screw up the ECU?

Wayne in FW

[TexasT]

First lesson, always take the negative off first, and put it on last. This lessens the inadvertent sparking he experienced. Most likely he did additional 'welding' inside the ecm.

Probably time for a trip to the wrecking yard for a new to you computer.

[Falcongunner]

First lesson, always take the negative off first, and put it on last. This lessens the inadvertent sparking he experienced. Most likely he did additional 'welding' inside the ecm.

Probably time for a trip to the wrecking yard for a new to you computer.

He knows betters. He grew up with me wrenching and building 50's and 60's Fords. I've had computers go bad before but never had one eat a large 20 amp fuse. Still wondering where to start diagnosing the short. Never did like the remove and replace troubleshooting method.


Wayne in FW

[AdRock]

Does the fuse blow if you just have the key in the RUN position without the car running?

[Falcongunner]

Does the fuse blow if you just have the key in the RUN position without the car running?

Haven't tried just with the key for very long but it does not blow immediately. The car starts and runs ok then surges a bit then "pop" goes the fuse and engine dies. Takes under ten seconds.

Wayne in FW

[034V]

unplug the ccrm and replace fuse. try in KOEO and see.

[Falcongunner]

unplug the ccrm and replace fuse. try in KOEO and see.

I'll try that. I thought I heard a sound over there by the ccrm just a millisecond before the fuse blew. By the way the 95 V6 was OBD II. GT was OBD I

Wayne

[Skidonenko]

When diagnosing multiple loads like that I like to install a fuse to each load. Working on the early sprinter vans they have splices with 8 or more circuits. In your with 2 Id start there, but with both units hooked up if the fuse does not blow with the engine off I would fuse each separately. I have seen too many ding dongs bypass a fuse only to burn an entire harness/destroy other items. You can only let the magic smoke out once, how much will vary.