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Abaker
06-06-2012, 02:50 PM
I have a 2000 Ford F250 V8 Gasser. Last week a really disturbing intermittent electrical problem started. It would just shut down for about a second and then reset. First the engine would die very briefly and then all the dash lights would light up like when you first turn on the ignition. It seems like the entire electrical system is getting shut off for a second and then comes back on. It happens randomly sometimes while driving and a couple of times while parked before starting the engine.

I hate these intermittent gremlins - they only show up while on the road not when the vehicle is in the shop.

If anyone has any advice on where to start trouble shooting this I'd appreciate it.

MaxHeadRoom
06-06-2012, 03:20 PM
Those intermittent's are the worst, the problem is that on modern vehicles all the various control modules are linked by a serial data line, it sounds like you are losing power momentarily to the main integration module?
I know on some GM's around that time, there was a problem with Ground connections that caused intermittent faults after a certain age of the vehicle.
A scan test may show something, if you have, or know someone with a code reader?
Max.

Bob Ford
06-06-2012, 03:21 PM
Look at wire connectors terminations. Some have a boot that slips on the threaded terminal. Had one like that engine died at some of the worse times, but as soon as you hit a bump/ door slam it was fine, Finally found it and just to cure any others I removed all boot type connections and replaced with lugs.

Bob

zipzit
06-06-2012, 03:46 PM
My guess would be bad ground (loose) somewhere, or an intermittent condition caused by something wearing thru insulation and causing a hot short to ground.

It would be nice to isolate which systems are having the trouble.. (that way you could isolate which ground to look for...) there are a lot of different grounds for individual systems on Ford vehicles.

If its absolutely everything at the same time its got to be related to high amperage ground at battery / block / frame. Has this electrical system ever seen water where it shouldn't have (e.g. did you buy it cheap from a used car dealer in New Orleans?)

It could also be a nearly dead battery tied to a poorly performing alternator...


--zip.

Frank K
06-06-2012, 04:24 PM
If the entire truck is losing power, take a look at the battery end of the battery cables. I had a similar problem once and found that the cable had corroded away INSIDE the lead cable end. Pretty much the only thing holding the cable in place was the insulation.

gambler
06-06-2012, 05:20 PM
check your ignition switch.

bewards
06-06-2012, 05:31 PM
correct me if I am wrong, but I think there is a main breaker under the hood also


bedwards

zipzit
06-06-2012, 07:47 PM
check your ignition switch.
er.. yeah... Funny story.

I sold a used car to a young lady who lived on base where I worked. I told her the car ran well, etc... She called me up the next day, said the car kept dying on her. I told her the car had been working perfectly for me. I came right over, asked her if I couldn't drive it for one day to determine the problem, if I couldn't find the issue and fix it I would give her her money back. She gave me a single key, I drove the car, took close look everywhere. Car drove great, no issues. Took it back next day. She calls me again, same troubles. I'm thinking 'no way'. Go back to her house, ask her to show me what she is doing, etc... She hands me her keys, sure enough car dies. I look at her keys, monster huge medal medallion on the key ring, very heavy! Bingo. I found a hairline crack in the ignition switch. My keys worked no problem, the weight of her keychain opened up the crack.

I think it was around $8 at the time for a replacement switch. Yea!

Mike Folks
06-06-2012, 08:04 PM
Yep, the monster, heavy keyring puts incredible loads on ignition switches. I read about a similar story years ago, but this time, the husband's key ring with all the keys was the problem. His wife's single key worked great, but not with his.

darryl
06-06-2012, 09:51 PM
Used to be there was a short wire going from battery negative to the body metal. I've seen several times where that connection goes bad- that's the main return for everything that uses the body for a ground.

wb2vsj
06-06-2012, 10:34 PM
My guess would be bad ground (loose) somewhere, or an intermittent condition caused by something wearing thru insulation and causing a hot short to ground.

It would be nice to isolate which systems are having the trouble.. (that way you could isolate which ground to look for...) there are a lot of different grounds for individual systems on Ford vehicles.

If its absolutely everything at the same time its got to be related to high amperage ground at battery / block / frame. Has this electrical system ever seen water where it shouldn't have (e.g. did you buy it cheap from a used car dealer in New Orleans?)

It could also be a nearly dead battery tied to a poorly performing alternator...


--zip.

My vote is also for a bad ground. Had a Ford Aerostar that did the same thing. Found that the ground cable that ran the electronics was loose under the hood.

flylo
06-07-2012, 12:48 AM
20 years ago I would say the dimmer sitch, seemed like everything ran thru it.

J. Randall
06-07-2012, 12:57 AM
If it were mine I would clean all the grounds first, and then go from there.
James

wtrueman
06-07-2012, 01:02 AM
Hi all: Maybe you guys remember the 1940's, 50's with Gus the mechanic in Popular Science. He solved this very problem. Wayne.

Tony Wells
06-07-2012, 01:46 AM
There are quite a few stalling complaints on that vehicle/engine on a tech site I have access to. Most of them point to either the COP or IAC. It would help if you could check to see if there are any codes set. Most of the chain auto stores here will pull the codes of there are any at no charge, hoping to sell parts. If you are still having problems after following up on the suggestions thus far presented, post any codes you can find and I'll see if there is a TSB or suggested fix or problem to pursue.

Abaker
06-07-2012, 09:08 AM
Thanks for the replies.

After doing some googling I found several cases where similar symptoms indicate problems with the GEM. I'm going to start with some of the more general suggestions and then if that doesn't do it focus in on the GEM.

I also found that Motorcraft sells access to complete shop manuals by online subscription. Might be kind of helpful to have wiring diagrams.

sasquatch
06-07-2012, 09:19 AM
Good plan to start with cleaning ALL grounds, then you have eliminated that to proceed further.

Yup, Ole "Gus" cured a lot of problems, (that was interesting reading,)

But poor ole Gus would be totally lost on vehichles today.
Those articles were very well written, i still enjoy reading them from time to time.

browne92
06-07-2012, 10:47 AM
An easy troubleshoot would be to hook a simple indicator light to any connection that comes straight from the battery (no key switch). If it goes out when everything else does, then you have a main power failure. If not, move it to the key switch side of things and repeat. This will narrow it down a bit.

Tony Wells
06-07-2012, 03:20 PM
For you "Model Garage" fans. (me too)

http://gus-stories.org/index.html


I can get you a wiring diagram if you like. PM me your VIN if you want one.

sasquatch
06-07-2012, 08:18 PM
Thanks for the very interesting link to the Gus Wilson site/stories.

Those stories related so much to a very experienced old garage operator, who had a reputation for patience, and figuring out difficult to diagnose automotive problems of the day. Most little towns had an older garage operator just like gus. (I actually worked for one at one time, very clever, patient guy.)

Just that ongoing series of stories i bet sold a great many Popular science magazines.

wtrueman
06-09-2012, 01:56 AM
As a kid on a small farm sixty years ago, this mag was part of our out. When I got to grade seven (high school) shop, there was a LOT of projects I wanted to build because of the power tools in the shop and Pop Science. Heck, we were able to melt and pour lead for projects! I don't remember face shields or other safety equipment. I have retired as a shop teacher now and sometimes sub at my school. The kids today AND the current shop teacher do not know or remember the things we had to do on a small farm just to keep equipment working. My "old" remembrances. BTW, I have saved and still consult my Pop Science mags from the 30's, 40's, 50's. Wayne.

Abaker
06-09-2012, 01:50 PM
When troubleshooting, I have a tendency to start somewhere in the middle and end up fixing unbroken things. Thanks to you all I started at the very beginning - the battery and that was where it ended. The battery was showing 12.2V - kind of weak, but taking a reading 1" up the corroded pos cable I got 9.4V.

Cleaned it, charged the battery and all is well.

I guess that the electronics like their voltage within a certain range and when it drops too low all kinds of interesting things happen.

Thanks again

browne92
06-11-2012, 10:59 AM
"I guess that the electronics like their voltage within a certain range and when it drops too low all kinds of interesting things happen."

True enough. I had a Toyota that didn't require an alternator light. When the alternator went out, EVERY warning light on the dash came on.