Code 24

Code 24 and MAP sensor output

Hello eveyone,

I'm kinda stumped here and I was hoping you all could help... I was driving down the road when all the sudden the jeep lost power. If I floored it it didn't do anyting, most I could get out of it was 1900 RPM. Check engine light came on also.

I got home, pulled the codes, and got code 24 - TPS circuit. I replaced the TPS and MAP sensors and have reset the ECU, the problem is still there - no power past 19K RPM.

My chilton's is about as useful as a pile of dog crap right now. It says test TPS termials 1 and 3 for 5volts but it doesn't say which two are 1 and 3. I assume the end ones since there are only 3 total. I'm getting the 5 volts there.

Next test impedence between batt. ground and neg. terminal from previous test. Result should be less than 5 ohms - ok there.

This is where they lose me... it says start motor, test voltage to the TPS, it should be 0.8-1.5 volts at normal idle. It doesn't mention anything about where to test this. Doesn;t mention termial #'s or anything. Am I supposed to just probe around until I find that voltage? What a bunch of BS!

If any of you guys have tested the TPS before, or havehad this problem, or even a code 24, please help me out. This guessing game is getting expensive. Heck if someone could post the haynes testing procedure that would probably be helpful.


Thanks eveyone

SimpleXJ

Well, I played around with it some more and figured out what wires are what on the TPS. Also tested the MAP sensor, and I'm getting too high an output from it. Should be .5-1.8 volts with throttle closed and I'm getting 3.4v. The old and new map sesnors both read the same. Anyone know what causes this?

Thank You

Surely the voltage they are looking is the throttle position voltage. This TPS is a simple potentiometer. You have already verified both ends of it as 0 volts (ground) and +5 volts. The place you should take the voltage reading is on the only terminal you have not yet probed on the TPS. That is the input signal to the computer.

SimpleXJ, the TPS signal wire should read from about 1v to 4v when the throttle is advanced, with the key on. I think the middle wire is the signal wire, as you've figured out. If you don't get a rise in voltage when moving the throttle, check the mechanical linkage where the TPS fits onto the throttle body. It might be broken or binding.