Ran into a puddle and my speedo died :(
I was driving on 94 west in Detroit, MI the other day and got into a hard to see road crack filled with water at 55 MPH. The noise of the water hitting the bottom of the truck was very loud. I got concerned it might have damaged something and half an hour later my premonitions came true:
-The cruise control shut itself off
- The speedo needle went to 0
- The odometer stopped spinning
The truck was running fine and I was still doing 57-58 MPH. The tachometer kept working... Some 10-20 minutes later the speedo came back online and I was able to engage the cruise.
After a while it got kicked out again. All in all, within 3 hours after hitting that puddle, this happened 3 or 4 times. A couple of times the truck also did sudden accelerations (1-2 MPH) with the cruise control on but after a couple of seconds, it went back to the cruising speed.
Then the rain stopped and everything worked fine. I stopped by TA at x.22 in Porter, IN to check the speed sensor on the transmission and they didn't find anything unusual.
Has anyone had something like this happen to their truck? On my 2004 International 9400, the truck's ECM is right next to the tire, on the front end of the engine towards the driver. I think the water got into the ECM or one of the wires and/or connectors near it and temporarily disabled the speedometer. When the water dried out, everything was back to normal.
I drove a whole day today (450 miles) and ECM and speedometer acted normal. Any comments?
Get some Termin8tor spray, the purple stuff, and spray the crap out of all the connections, terminals and check the harnesses really carefully for any knicks in wires.
Water into the wiring is the beginning of the devil's spawn, so get it sealed up and keep it out, cuz the salt gets in there next...
Spray has got to be a water displacing dielectric.
Lightblue Freightshaker :thumbsup:
Speed Sensor in the trans could have gotten wet or is going bad.
Thanks for a good tip. I'll also stop by CAT and have them check all the wires and harnesses under the truck next time I do oil change.
Originally Posted by LBF
It's probably the darn water shooting at the truck's bottom at high speed that's to blame. As I mentioned I drove the entire day today and the speedometer worked like clockwork. BUT: it was a sunny day in WI and MN.
Originally Posted by boneebone
Speed sensor is my bet. But getting the ecm checked and cleaning all the connections can't hurt. The speed sensor controls all three of your problem areas.
Tough times don't last..Tough people DO!!! Trojan S.C.D.
I have had the exact same symptoms happen to me before. though not from any water. trucks are made to go thru severe rainstorms without disabling things. mine surged with the cruise on too. it was loose or bad cable/ wire. I had replaced the speed sensor in the trans & that seemed to fix it.
however that only fixed it temporarily. cause the sensor was not the problem.
it was the wiring that was causing the sensor to keep going out. I replaced all the jumper wires on the batteries & both main, hot & ground cables & cleaned all ground connections down to the bare metal. I had the e.c.m. wiring harness replaced a while back , so I knew that was o.k. I have went thru heavy rain & deep splashing puddles, speedo has not gone out because of it. I.M.O. I dont think it was the water itself. more likely the water pressure cause a connection to lose contact.
one reason I knew it was not the sensor is cause my engine light came on & when I had the e.c.m codes checked, it had all kind of false codes, due to the electrical short. & the speed sensor going out would not bring up all the false codes. I am not sure wich cable or cables that was causing my prob, so I replaced them all. by your description of the events. I would say it is in the wiring somewhere. not the speed sensor. though keep in mind. that bad wiring can make the speed sensor go out quick. so you may have to fix the electrical short plus the speed sensor.
Back in 95 I ran through a puddle on NB I-5, just coming off the ship canal bridge. The engine died right then. Managed to coast about 300 feet, enough to clear half the left lane onto the shoulder. ECM on the truck was bad (a brand new T-800). I was loaded with 11,500 gallons of gas, and the wrecker service sent out one of those little roll-off jobbies the first dispatch...to try and pull me out of the way!! Yeah right!!! :rofl: :rofl: :rofl:
Space...............Is disease and danger, wrapped in darkness and silence! :thumbsup: Star Trek2009
97% of ecms turned into the factory from dealerships are not bad...very very rare ecms go bad,
the water cased wires to move possibly pushing wan exposed or loose wire.
too many times merely the act of tightening connections solves many problems.
look at the wire connector ( pull apart) and look for some green corrosion..
The transmission yoke that the mechanic speaks of is the part that attaches the universal joint (at the front of the driveshaft) to the transmission output shaft. On the outside diameter of the yoke is a "tone wheel" which looks like evenly spaced teeth on the yoke. The VSS (Vehicle Speed Sensor) is mounted with it's probe in very close proximity to the tone wheel. As the trans output shaft (with yoke & tone wheel attached) rotates, the VSS creates a pulse each time one of those teeth on the tone wheel passes by it. These pulses are "read" by the ECM which sends a signal to the speedometer based on how many pulses are occurring in a given amount of time, causing the speedometer to display your MPH (or KPH).
Since the VSS is in such close proximity to the tone wheel on the yoke, a loose yoke can cause the tone wheel to actually strike the VSS probe, destroying the VSS. When that happens, the ECM puts your engine into "limp mode" since it is no longer receiving a signal from the VSS.
If you can't shift it smoothly, you shouldn't be driving it.
Thanks. I understand better the workings of a speedometer now. I've been doing research on Internet and compiled a short "cheat sheet" that I"m going to give to the mechanic tomorrow. Here's what I have so far:
Originally Posted by Kranky
"DEAD SPEEDOMETER & ODOMETER
- wiring connectors, incl. those on the firewall (loose? corroded?)
- bad ground
- speed sensor and/or sensor plug
- transmission yoke and rear tranny cover
- ECM chassis harness
- frayed wiring/shorts somewhere between the VCC and ECM
- loose fuses/moisture in the fuse box
1) The tranny had some work done on it in January 2009 and was taken out and then put back in.
2) The windshield was replaced in July 2009.
3) I sprayed all wires/connectors with the Termin8or after the speedo died the first time about a month ago."
If anyone can think of any more causes, please let me know - I'll add them to the list for the benefit of the International Trucks mechanic. Thx!
i'm back from the dealer. they took the speed sensor out and found a very small crack in it, which wan't evident when the sensor was inside its socket. replaced the sensor. the speedometer is as good as new