School me on Throttle Position Sensor (1993 HDJ81)

lumpy70

 
Joined
Nov 6, 2004
Messages
865
Location
Calgary
So I'm getting an error code 41 from my O/D light, and I don't have torque converter lockup since my injection pump rebuild.

The Error Code 41 is: Throttle Position Sensor. I did the resistance test on it and it ohms out ok. The wiring harness seems ok, and I've already (foolishly) replaced the ECT and the O/D solenoid before I actually read the trouble code.

Questions:
  • After the resistance test, does that mean it works 100%?
  • Is it fixed or adjustable?
  • Does it have any connection to the Injection Pump?
I've looked up in the Body and Chassis Manual, the 1HD-T manual, and the A442 manual; and there is no reference to the Throttle Position sensor that I can find.

Should I just replace this part on spec?

Error Code 41.jpg


Error Code 41 Repair.jpg


Throttle Position Sensor.jpg
 
Joined
Mar 9, 2009
Messages
265
Location
Central Queensland, Australia
I have found Va and Vc pins are swapped around on my TPS and on a mates also???
Regardless, have you done the voltage test? 5V power supply required.

It is adjustable by loosening the 2 mounting screws and rotating the sensor on the injection pump.
It is adjusted to provide a voltage reading at full throttle, not no throttle. I can't remember 100%, I think it is 0.8V at full throttle. About 3.4V at no throttle.
I would recommend marking the current mounting position and removing the sensor off of the pump just to make sure it is sitting on the throttle position tab things properly. This is easy to get wrong. This is the connection to the injector pump.
 
Last edited:

IanB

SILVER Star
Joined
Jan 23, 2010
Messages
4,189
Location
Winnipeg, MB
The TPS is for the electronic transmission only, doesn't play into the engine stuff at all.

How did you confirm you're not getting TC lockup? I remember there was some confusion on how it all worked in another thread. Should lock up in 3rd and 4th (OD) at about 85km/h in my experience. Easy to test in 3rd (OD off) as it feels like another gear shift and you can watch the tach.

Which manuals are you looking at? If they are earlier versions they won't have any of the electronically controlled transmission stuff as the early A442F's were fully hydraulic.
 

lumpy70

 
Joined
Nov 6, 2004
Messages
865
Location
Calgary
Since the IP rebuild the O/D light was flashing, I went thru the diagnostic procedures and it gives me an 41 code.

It's definitely not giving me that last "shift", RPMs are about 150-200 higher at Hwy speed than before the rebuild.

I have the A442f electronic transmission, the FSM's I'm referring to pertain to my truck year and transmission.

I'll post a copy of the manual cover when I get a chance.
 
Top Bottom