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2000 XJ TPS issue

a_ibrahem

NAXJA Forum User
Location
Dubai
Hello everybody ,

am new here to the forum and to the XJ also ,
i have 2000 I6 AT XJ ,

it has P0123 code ,

my XJ has one socket to the TPS with 3 wires
as i understand the wires are :

1- TPS ground
2- TPS signal to PCM
3- 5 volts from PCM

i unpluged the connector to the TPS sensor and measured with the fluke while ignetion key in ON position

i have 5 volts on wire 2 and 3

my question : wire 2 is signal from TPS to PCM so why there is 5V on the wire all time ??

please advise.
 
ok after reading some of the threads ,I went down and measured the voltages again

1- TPS ground
2- TPS signal to PCM showing 5.6 volts
3- 5 volts from PCM showing 5.1 volts
code p0123 and not clearing also

then as many mentioned I removed the horn relay and measured again
1- TPS ground
2- TPS signal to PCM showing 4.6
3- 5 volts from PCM showing 5.1

and now when clearing the codes with scan tool its gone

so what is the issue with that horn relay ,am not able to find how its interlinked ?
 
Typically a P0123 is a TPS fault. If removing the horn relay prevents the Trouble Code from reappearing, you have clock spring or steering column wire harness issue. The horn and the TPS share a ground connection. If a short circuit involves the ground wire, you have high voltage on the TPS.

P0123 Jeep - Throttle Position Sensor Circuit, High Input

Possible causes

- Faulty throttle position sensor
- Throttle position sensor harness is open or shorted
- Throttle position sensor circuit poor electrical connection
 
hello guys ,

thanks for your support ,yes removing the relay cleared the codes and also it stops hesitating while accelerating. it runs very smooth now

how can i diagnose more the problem ?
how to make sure its the clock spring before buying new one ?

and if its just that they share ground if i separate them (if it’s possible) will this solve the issue ?

regards,
Ahmed
 
Last edited:
Unplug the clock spring and plug the relay back in. If the problems does not return, the clock spring should be tested for failure.
 
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