Posted - 01/14/2014 : 08:20:13 AM
| Hoping you all can help a bit here:
Working on a 2004 IH 4700 DT466E. On Christmas Eve, it was making a long run, and the truck lost throttle response. The driver (Driver A) pulled of the side of the road, shut the truck off, and then restarted it- all was fine for the rest of the day.
Back in the shop, I get the following codes (in this order) :
134- Accelerator pedal and idle validation disagree
133-Accelerator pedal in range fault
135- Idle switch circuit fault
222- Brake Switch circuit fault
I run a visual check of all the wires, and don't see anything out of the ordinary, and driving myself- I am unable to duplicate the issue. So I replace the Throttle Position Sensor.
Truck goes out with Driver B and C on different days, and has no issues.
Saturday, January 4, Driver A is again driving, and the truck has similar issues 3 times during the day, and again throws the above 4 codes.
Bring it back to shop, all checks good, can't duplicate the issue. After a long road test, I send on a short run with driver D, and all is good. Driver B takes it on a long run, and again all is good. Check for DTC codes, and all is clear. It goes out the next couple of days, and all is good-
Until Driver A drives it again the next Saturday. Truck looses throttle response twice, and throws the same codes again- all 4 of them.
I just got it in here, after a 20 mile test drive, and no issues and no codes. I am perplexed here. Could this one driver be driving in such a way that he is stumping the TPS?? lol, that sounds crazy, but he is the only driver in the last month to have issues in this one truck.
Couple of things to make note of:
-Driver A drives with both feet- one on the accelerator and one on the brake. I have begged him to stop, but he refuses. You can follow this driver and hardly ever see the brake lights go off.
- To combat the dreaded IH brake switch faults on these trucks (and having to deal with crappy IH brake switches,) my company put in a brake wiring kit that puts a Ford brake light switch on the pedal that presses up against the booster head to activate the brake lights. I've yet to have an issue with them, but there is no matching up switches, or adjusting this particular switch.