Hello, I am new to this forum and hopeing somebody can help me.
02 f250 SD. While driving, sometimes the battery light blinks slightly and the headlights seem to flicker just a bit. Then all the gauges go crazy. The spedo sticks to however fast I was going, tach falls and stays on zero, all of the other dials fall and stay on zero, radio shuts off, Headlights stay on, trucks keeps running fine, then there is a slight "click" and ALL of the gauges cycle all the way to the right and then all the way to the left and then go back to normal operation. Does anybody have a clue on what the heck this could be? a loose connector? bad relay? Im just shooting in the dark here. Please ask any questions. Its done this in the rain and while dry. Only while driving, never just idleing. Engine light does not come on. No mods to the truck.

Thanks in advance folks!
Joey

 

Check all your grounds, particularly at the battery, for looseness or corrosion.

 

Thanks for the reply BareBones. I did check, clean and tighten the battery connections. What other grounds might I look for?

 

The engine especially. Its a big chunk of iron, but it sits on engine mounts that are made of rubber, so it has to be connected to the chassis with a grounding strap.

However, I'm going to SPECULATE based on what you've said being correct, that your problem is localized to the dash display, probably sopmething along the lines of having a water leak which maybe is causing corrosion somewhere like your fuses.

I say this because you've indicated that the vehicle continues to run fine while experiencing your "ET Phone Home" moments, and if your computer were rebooting then you'd surely notice an operational problem.

One more thing. In checking battery connections, people tend naturally enough to check the terminals at the battery. However, one of the cables will run to the chassis, so check that connection too.

 

Before you get too far along in tearing out the dash.....check the output on your alternator. I had approximately the same reaction when the alternator on my '06 decided to crap out.

Just a thought, and it's an easy thing to check....

Good luck and let us know what you find...

 

I just went through the wiring diagrams in the Haynes manual. It doesn't have the wiring for the instruments (just intrument lights), but it does have the radio wiring. There is a delay relay that powers the radio, but it doesn't have anything to do with the intruments. I see no relays common to both systems.

Then I looked at the Ford Factory CD with the electrical troubleshooting information on it. There is no common ground for the intsrument microprocessor but they do share a common fuse. The fuse is listed as F2-27 which is a 10A fuse located in the central junction box. I have had fuses that developed a hairline crack, from vibration, and were intermittent in nature. I'd swap that fuse for general principles.

The fuses for the instruments are F2-8, 16, 18 , & 27. For the radio it's F2-11, 12, & 27. There is one common connector labeled C270d which connects to four items: Generic Electronic Module, Instrument Cluster, Audio Unit, and Date Link Connector. This connector is located under the glove box area. I can't seem to get the picture to copy to here. I have it in a word document and a pdf, but I can't get it to paste here.

Anyway, that's the only common link that I could find between the audio and instrument systems. There are two grounds on the intrument microprocessor and one on the audio system and they are not in common. That certainly doesn't mean that the ground connections on the battery or engine could not be the problem. Intermittent problems are very hard to find. Good Luck! Mike

 

You know, speaking of hairline cracks, there were a couple of posts here recently about the underside of the fuse box in the engine compartment (driver's wheel well) that was corroding and causing intermittent problems, though I don't remember what they were exactly. To check this out I believe all you have to do is remove a couple of screws and look on the underside of the fuse block.

 

Hey guys thank you for all of the suggestions. I will run thru each of them. Boy, I've got some homework to do this weekend. I will surely post any findings.

Thank You,
Joey

 

I went thru all the fuses inside the cab and didnt find any problems. I looked for the fuses in the engine compartment above the left front wheel well but all I see is a few connectors mounted directly to the wheel well. I have not checked the alternator's output yet. I dont know how to do that so I'll read up on it. Since its been rainy, Ive driven the truck to work this week. Monday it did the mystery dial dance and I noticed when I turned the truck on early in the morning the headlights pulsated a bit. Once I got on the road . . . dial dance. But yesterday and today, nothing, no dance. Very strange. I normally ride my motorcycle to work and I have gone a week sometimes without driving the truck. I wonder if that might have something to do with it. It cranks right up though, so I dont see how that would be a battery thing. Anyway. Just want to keep you guys posted and thanks for your inputs!

 

You are getting to the mileage where the alternator brushes could be getting to their end-of-life. They get erratic as they go away, and possibly cause "dirty" buss voltage spikes. Dirty voltages play hell with any processor-controlled circuits.

The power delay relay that the radio is on is timed by a "processor", so maybe that's a clue.

The headlights not outputting consistent lumens is another clue of voltage irregularities, again pointing back to the regulated output from the alternator.

Just some thoughts....

Pop

 

The first step in checking the output of an alternator is to take it into a parts place like AutoZone, where they will do a load test for free......

 

I think one of the first steps would be to hook up a DVM to the output terminal and see if there's somewhere around 14.4 volts there.

That might save some time going to the parts house.

Leaving the meter on while running it through a few "paces" will tell you something about the condition of the thing.

What happens when the lights are cycled on and off?

Is there a difference when the glow-plug relay (if you have one) turns off?

If yours is a diesel, however, don't expect the full 14.4 until the glow plug relay turns off, as it draws a lot of current when on, and will load the alternator to the point it can't produce enough current to maintain that voltage.

Pop

 

I'm having the same exact problem with my 2002 F-350 7.3L diesel and I just replaced the alternator, serpentine belt and all pulleys and it fixed it for 2 weeks and then it came back with a vengeance. Grrr.

 

Hey guys, Well I took the alternator to the autoparts house and the thing failed miserably. The alternator I replaced was not the original one. hmm. I put another one in and everything seams to be okay. Now, Montana's F350 is doing the same thing after two weeks of replacement. I will let you know if the dancing dials come back. Is there something the truck could be doing to trash alternators I wonder. Again, Thank You for all the replies and suggestions!!!