I haven’t used my truck in about 8 months. Took off in it Saturday pulling a trailer. After a while I realized the odometer and Speedo were not working. Then the tranny started shifting real hard. I didn’t have time to mess with it because I was on a tight schedule this weekend. I just parked it. Is there a fuse that controls these? Would that cause the tranny to go into limp mode and if so will replacing the fuse bring it out of limp mode or does it have to be reflashed or something? I have no experience with this type tranny. Thanks in advance.
Think my tranny is in limp mode?
- Thread starter Figor
- Start date
BeastMaster
Full Access Member
Most likely, your problem is in the circuit feeding your speedometer. Your speedometer tells your transmission controller how fast you are going.
Without knowing how fast you are going, your transmission controller goes into limp mode.
Check the VSS circuit... (Vehicle Speed Sensor).
You have come to the right place. A lot of people here are very familiar with your woe. It's usually a bad or dirty VSS sensor. And most likely your transmission is unharmed.
If you were towing, have you been having any wear/grinding issue with your rear end? I had an issue with mine where the differential oil had become contaminated with metal shavings, which fouled and magnetically short circuited my vss sensor, which on my van is mounted on the differential and picks the speed signal from magnetically sensing gear teeth in the differential. Upon removing my sensor, it had appeared to have grown a head of hair, but it was metal filings. But my problem was elsewhere, in the speedometer module itself, and had to be replaced.
Without knowing how fast you are going, your transmission controller goes into limp mode.
Check the VSS circuit... (Vehicle Speed Sensor).
You have come to the right place. A lot of people here are very familiar with your woe. It's usually a bad or dirty VSS sensor. And most likely your transmission is unharmed.
If you were towing, have you been having any wear/grinding issue with your rear end? I had an issue with mine where the differential oil had become contaminated with metal shavings, which fouled and magnetically short circuited my vss sensor, which on my van is mounted on the differential and picks the speed signal from magnetically sensing gear teeth in the differential. Upon removing my sensor, it had appeared to have grown a head of hair, but it was metal filings. But my problem was elsewhere, in the speedometer module itself, and had to be replaced.
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I don’t do much towing. I was just taking an empty trailer to a friends house. I is a pretty large triple axle trailer. But in general I don’t use this truck to tow with. I mainly use it around here to lift stuff with the crane. That may be part of the problem. Not using it enough.
I’ve been having mice issues. Lost my 1986 BMW 524td and my 2002 Aprilia ETV1000 to mice chewing through the wiring harness. The BMW caught on fire. I think I can fix the Aprilia I hope.
I’ve been using bait block poison but lately it doesn’t seem to be working as well. I hope they didn’t get in this truck. I haven’t noticed any signs. I’ll look into the VSS circuits. Unfortunately I’m not very good with the electrical stuff.
I’ve been having mice issues. Lost my 1986 BMW 524td and my 2002 Aprilia ETV1000 to mice chewing through the wiring harness. The BMW caught on fire. I think I can fix the Aprilia I hope.
I’ve been using bait block poison but lately it doesn’t seem to be working as well. I hope they didn’t get in this truck. I haven’t noticed any signs. I’ll look into the VSS circuits. Unfortunately I’m not very good with the electrical stuff.
Jesus Freak
Full Access Member
I have a small farm (6or7 dairy cows, few horses, @150chickens, 4 bulldogs)and part of that farm is cats. About a dozen cats male and female, they regulate their own population. But one of my whitisisims is, "when you have a farm, either you have cats or rats. I prefer the company of cats". I'm very sad about the Beamer, I would gladly donate a bucket full of cats to help. And HEY! If you convert to a zf5 you won't have electrical issues.
Cant Write
Full Access Member
@Figor on my van, the people who did all the aftermarket wiring for the government tied into the fuse that feeds the speedometer and odometer. I shorted wires and tripped, and it took the same things as you mention, and my trans went to full line pressure when shifting. On my van, 1992, there is a 15 amp fuse serving it. Found the fuse, and the wire. Replaced the fuse and continued on my 2000-mile journey with everything working again. Oh it also killed my CC, which how can one live without CC on a long road trip 
Regarding mice, are you in a place to leave your hoods open? That is best if you can. I do not have a garage and everything starts nesting come fall, and they (mice, chipmunks) love the residual heat of my diesels. I have had to rage war on them and I usually leave the hood open when I get home to cool it faster. And then have multiple flood lights lighting up the underneath of my vehicles and engine bay. (lights are very low wattage for lumen output these days) Traps sometimes work but it takes diligence, multiple traps, and tuning them to a true hair trigger!!
I would love outdoor cats, but then I attract mtn lions and bobcats. Last summer we had a mtn lion that would park itself on the neighbors deck and stare in through the window at the indoor house cat. Last winter about 2 in the morning I went out and grabbed firewood, looked up and across the dry creek was a mtn lion looking to make me a meal. That raised the hair on my neck. Not more than 30' away. I kept my light on him and slowly backed to the house.
Regarding mice, are you in a place to leave your hoods open? That is best if you can. I do not have a garage and everything starts nesting come fall, and they (mice, chipmunks) love the residual heat of my diesels. I have had to rage war on them and I usually leave the hood open when I get home to cool it faster. And then have multiple flood lights lighting up the underneath of my vehicles and engine bay. (lights are very low wattage for lumen output these days) Traps sometimes work but it takes diligence, multiple traps, and tuning them to a true hair trigger!!
I would love outdoor cats, but then I attract mtn lions and bobcats. Last summer we had a mtn lion that would park itself on the neighbors deck and stare in through the window at the indoor house cat. Last winter about 2 in the morning I went out and grabbed firewood, looked up and across the dry creek was a mtn lion looking to make me a meal. That raised the hair on my neck. Not more than 30' away. I kept my light on him and slowly backed to the house.
Yeh I’ve been battling mice for 20 years. Somebody dumped a cat here a few years ago but I got rid of it. Coyotes were trying to get it. Wish they’d get on the mice.
Well the reason I first asked about the fuse is because someone had jumped a wire across some fuses in the fuse box. I noticed it was really hot one day a few years ago. I could smell it getting hot so I unhooked it. Now I can’t remember where it was jumped. Everything still worked after i pulled it so I didn’t think much about it until this happened.
This truck is an old Case tractor service truck so it has a lot of wiring added. Two way radios, spotlights and then all the crane stuff.
As far as a ZF5, well I’d sure like that but I really can’t afford to do that conversion right now. Especially since it costs $225 to fill my Dodge a few times a week. Thanks to Biden…
Well the reason I first asked about the fuse is because someone had jumped a wire across some fuses in the fuse box. I noticed it was really hot one day a few years ago. I could smell it getting hot so I unhooked it. Now I can’t remember where it was jumped. Everything still worked after i pulled it so I didn’t think much about it until this happened.
This truck is an old Case tractor service truck so it has a lot of wiring added. Two way radios, spotlights and then all the crane stuff.
As far as a ZF5, well I’d sure like that but I really can’t afford to do that conversion right now. Especially since it costs $225 to fill my Dodge a few times a week. Thanks to Biden…
Jesus Freak
Full Access Member
Bulldogs and cats keep everything away, or at least hold it down long enough to shoot whatever it is. That's been my experience, but it usually seems my experience is different.
