Bear with me, this may be long, just want to give all info I can...

I recently bought a 2000 F250 4x4 CCSB V10, it was about 400 miles from home, about 50 miles into the trip I wasn't sure I was going to make it!

Here's what happens, all gauges work great, then was on the highway and noticed the voltmeter jumping around, I was on a rough road, but didn't make the connection between that and the jumping around of the gauge. I watched it for 10 miles or so, then it settled at around 10-11 volts, then the CEL came on. It stayed this way for the next 20-30 miles until my next stop. I pulled off the freeway and noticed when I apply the brakes the gauge went to zero, let off and back to 10v or so. Tried my blinkers and the gauge didn't move. So, I'm thinking bad alt or short/loose wire or something.

Anyway, I borrowed a voltmeter and checked voltage at the batt, it was 12.6 or so with truck off, then fired up the truck, went up to 13.8 or so. Ok, so I'm somewhat comfortable where I know it's charging at least. So about 20 minutes pass (truck off) and I start it up for my drive home of still more than 300 miles. Gauge is up around 14v now and solid. I keep my eye on it every so often and it stayed solid, never moved, made it home without any problem. By the way, CEL went off and didn't come back on.

Fast forward a few weeks, keep in mind I don't drive this truck, it will just be my tow vehicle, so I haven't driven it much at all since I got it. I need to get it smogged, so I drive about 12 miles to the smog station and the gauge starts fluctuating again and is doing the same thing as before, but now I notice it seems to move with every bump I hit, smooth road, no movement, bump, it moves, lots of bumps, it moves a lot! I'm thinking I won't pass smog if the CEL comes on again and was ready to abort and head back home. It's good so far, so I pull into the smog station, get in line and about 2 min later, the light comes on!!! Damn it, now what?!!? Well I shut the truck off and leave it while I wait. Cars start to move and I fire it up, gauge is low again, but CEL is off and I go to put it in drive and nothing, the shifter won't move, I hit the brake again, still nothing!! Ok, now what? I shut it off and restart, same thing, damn, now I'm really screwed!! I didn't know what to do, but just thought, hit the parking brake and release it, ok, try that, apply parking brake, pull lever and release, it slams up and gauge goes up to normal and I can now shift!!! What's going on?

Everything was fine after that, truck shut off and started 3 times and I drove home with the gauge rock solid normal, no CEL.

Anyone experienced this before? Where do I start looking, is it the brake pedal switch? How would that affect the voltmeter? Why does the CEL come on?

Also, how to I get it out of park if this happens again before I fix it? Is there something I disconnect to trick it into thinking the brake is on when it thinks it's not?

 

Wow what a mess....I would check all connections everywhere. You have an issue and it won't go away. Chances are it will get worse. Have the battery load tested. Wiggle wires with eng running and someone watching gauges...emer brake can't do anything on a 2000.
Unless you have a loss of power to the shift interlock circuit. bad ground or bad connection to the cab of the truck like the gauge circuits or whatever fuse powers the shift interlock. I'm thinking the engine isn't seeing this problem. IMO..

Dick

 

Yes this is a mess, there are other issues too, but this seems to be the only electrical issue.

I'm sure the parking brake has to be related, maybe not directly, but more that when it's released, the jolt shook something near it that might be the problem. I will check wires and grounds down there, but just looking for a direction more than checking everything!! The parking brake has to be connected in some way, the second I released it, the gauge went up to normal, so the connection was made.

Come to think of it, the first time it did this, I set the parking brake when I parked it, when I left I had to release it and set it a few times as the rubber bumper was bad that hits the switch and the brake light wouldn't go off. Setting and releasing a few times usually got it in a position to depress the switch. So, not directly related, but could be something with the movement of the pedal or just the shock when it's released and slams up. I put a new bumper on the pedal arm, so that isn't an issue anymore for the brake light switch.

I'll check under the dash in that area to begin with, I've already checked the batt and alt connection. I sort of ruled that out in the beginning as even when the gauge was low, the batt was much higher and was charging. So I'll focus on the connection to the gauge and somewhere under the dash until other ideas are thrown out there.

 

Update, still no solution, need more help with another problem though!

I've driven the truck a few times since my last post and the gauge has never given me a problem again, but now I have a new problem...

First off, I found a solution to the problem of not being able to get it out of park when it's not sensing the brake is on. You just turn the key one click, just before "on", no lights or anything come on, but you can shift into neutral, once in neutral, you can then start the truck, then into gear, don't go back into park or you start the process over.

Now my new problem, truck will occasional start then die instantly or not start at all. The idle is a bit irregular, so I was leaning toward the IAC. I had this problem a few times, but it always cleared up after one or two tries. I plan on replacing the IAC, but today I washed the truck (outside only) and went to start it to move it back to the side yard and it started and died, then it wouldn't start at all. Probably 10-15 tries in 10 mins. I tried hitting the IAC with a screwdriver handle to see if it would free up, but no luck. Then I thought of the fuel pump, I turned the key to "on", no pump whine, tried again, nothing, the pump was silent. So I got a mallet and hit the tank a few times, tried again, nothing, hit the tank harder, tried again and pump is on, try to start and she fires and runs. Coincidence? I'm leaning towards fuel pump now.

Question though, is there anything else that would cause this? Fuel pump relay perhaps? Is there any way to check unless it fails again?

Honestly I don't mind changing the pump out, at 130k it couldn't hurt, but I want to find the problem instead of just throwing parts at it!!

 

I wonder if your having an Ignition Switch Issue
Haven't had to change 1 on a SuperDuty but on many other vehicles ive worked on there's a Switch mounted halfway down your steering column (the actual Ignition Switch) that controls Engine Starting (in proper Park/Neutral positions), Key Acc, Run position & if its broken/shorting-out all kinds of weird issues happen (ie..Starting, Powering of Circuits).....Just a thought

 

maybe a ground problem..

 

Pull the fuse box on the drivers side in tha cab down and see if there is evidence of water. I am betting on a leaky windshield causing all these issues.

 

Yup bad pump...

 

Completely forgot about all the water and GEM issues with these trucks. Took a look under the dash today and saw no evidence of water anywhere. I did find a few wires that have been tampered with though.

First is a light green wire coming off the brake switch, there is a scotchlock (I will never use those, I hate them!!) on it with another wire coming off that has been cut. I'll take the scotchlock off and solder the wire back together. That could be the shift interlock problem, but why would it affect the voltmeter?

Second is maybe four wires coming off the harness that also goes to the DLC. Not sure what they do, but there are butt connectors and then cut wires on the other side of the butt connectors.

Back to the possible water leaks, do I have to pull the fuse box to see inside or behind it for corrosion or anything? Or would I see water damage under the carpet and under the door sill if water was getting in? And if I have to pull it, what's the easiest way?

 

I personally have never been in to my GEM, all I know is what I have read on the internet .

The way I understand it the GEM is behind the fuse box on a 2000, sometimes you have to open the GEM to see the corrison.

 

**Update**

I installed the fuel pump and that seems to have solved the starting/running issue.

Also, the voltmeter/power problem went away for a few months, but now it's back. I was running some wires under the dash and through the firewall and had the battery disconnected. Next time I started the truck, the gauge was at 9 volts and the check engine light came on. I was able to pull code p1633, keep alive power low or disconnected. At least I have an idea of where to check now.

I found some wiring diagrams and I'm going to check the voltage/wiring, does anyone have any experience with this and can give any tips on what to check?

Also, I was tapping into the dimmer wire for the dash lights. When you turn on the parking lights, the chime rings to let you know they're on. After pulling out the headlight switch and messing with the wiring, the chime didn't ring, then it started ringing again, could this be related?

Another question, I read somewhere about an alternator problem that was finally fixed by disconnecting the wire from the alt to the fuse box or whatever will signal the voltmeter, they ran a new wire to the voltmeter and that solved the problem. If I find low voltage and can't figure out why, could I run a new wire for the voltmeter/pcm signal? If so, where do I tap in? I know the alt is working and the battery has good voltage, the drop is somewhere between the alt/batt and signal for the voltmeter.

 

I'll add on to my previous post, I checked everything I could today.

I checked all the voltages at battery and fuse boxes. One thing that has me stumped is I first checked the batt, it showed 14.5v (truck off, not charging), then checked again, 13.5, then again, 12.6, this was all within 30 seconds. Went under dash and checked a few fuses, again, got high voltage the first time, then dropped to normal.

I went ahead and charged the battery while checking all the grounds I could find. There is a ground behind the drivers side kick panel that is for the shift interlock relay, I removed it and cleaned it and it seemed fine, but when I mess with the ground (like making contact and removing it), the relay clicks, should it make any noise without applying the brake to activate the relay? Remember, one of my problems is when the voltmeter shows below 10v, I can't shift out of park, also, when I apply the brake, the voltmeter drops completely. Is any of this on a related circuit?

All the wiring and grounds look good under the dash, at the firewall, all connections I could find, everything. I went ahead and pulled the pcm to check pin 55 which is supposed to be the KAM power, hot at all times. I had no voltage. There is voltage at the fuse that supplies power to the PCM, so there should be voltage here, not sure where to go from here. I'm tempted to splice a new hot wire in, but don't know if that would solve all my problems or just the P1633 code.

It all has to be related, I only have all the problems, not just one or another. And now it's not intermittent, it's doing it everytime I check it, which is good for diagnosing, but bad since I can't find the problem!!

I'd like to get this figured out soon, I have a trip coming up and don't want to get stranded 200 miles from home in the middle of the desert, that would be an expensive tow bill!!

Any help/advice is appreciated!

 

I see this last update post was in Jan 2014.
Was this resolved?

 

Yes it was resolved finally!! Sorry, completely forgot this thread. Are you having a similar problem?

Turns out it was a loose connection inside the fuse box. I searched everywhere before focusing on the wires that had anything to do with the circuits I was having problems on. I removed the fuse box and one of the female terminals in the box was loose, there was no tab/detent to hold the terminal when the plug was connected, there was no way to make the connection tight. This had to be a problem from the factory and it finally worked it's way loose, there was no sign of this area ever being touched, but who really knows when and why it came loose.

Anyway, for the fix, I tried a few different things from silicone to regular epoxy and nothing would hold. I ended up getting some marine grade epoxy that was designed for plastics and shoved some pieces of zips ties in to tighten up the terminal with the epoxy to secure it all in place. It actually worked!!! Put it all back together and have never had the problem again.

Pulling the code got me focused on the right area and access to the wiring diagrams showed me where all the connections for the circuits I was having problems with were. I can't even imagine how much this would've cost to have a shop or dealer diagnose!!

I'm just glad it's fixed, I can finally be confident in this truck being reliable.

Thanks to all who helped me focus in the right direction and get this issue resolved!

 

Yes, I have been having a problem with my 2000 F250 in that my Headlights sometimes don't come on when starting the truck. I have to hit the light switch off and on again several times to get the lights to actually come on.
Sometimes I have to turn off and restart the truck to get the headlights to come on.
I also have a 2008 EB Explorer that has dash warning lights randomly flashing while driving. I've replaced the ignition switch (electronic portion, not the cylinder) I've given it a new battery and tested the alternator at a local auto shop and it tests good so maybe it's time to start going thru the fuse box.
Thanks for getting back to me with the resolution that worked for you.