Having issues with my TJ

[Steven.Boyd]

Hi Heidi

Thank you can you please PM me your number so i can give you a call to organise to borrow it

Thank you

[Steven.Boyd]

The following codes come up on the dash
12 24 21 55

Any ideas ?

[SteveC]

Steve. It shld be inlots of 4 numbers

[Steven.Boyd]

Need help turning the codes in to laymans tearms and what to do to fix them

12 Direct battery input to PCM was disconnected within the last 50 Key-on cycles.

21 Upstream oxygen sensor response slower than minimum required switching frequency. Upstream oxygen sensor heating element circuit malfunction. Downstream oxygen sensor heating element circuit malfunction. Downstream oxygen sensor input voltage maintained above the normal operating range. Oxygen sensor voltage too low, tested after cold start. (Upstream or Downstream) Left oxygen sensor input voltage maintained above the normal operating temperature.

[Steven.Boyd]

24 Throttle position sensor input above or below acceptable voltage. TPS signal does not correlate to MAP sensor.

I guess this means I need a new TPS sensor

[Steven.Boyd]

I have tried doing some tests and this is what i have come up with

did the on off on off on test an got the following codes 12 24 21 55

so i unplugged the Throttle Position sensor and tried it again and the same numbers came up

The engine idled at normal RPM with the TPS unplugged but was very lumpy

Then tried a Scan Gauge and got the following codes PO123 & PO132 still with the TPS unplugged

Cleared the codes on the scan gauge and scanned again and it came up with no codes

Pluged the TPS back in and engine idled at around 2000-2300 RPM

Tried the on of on of on again and it came up with 12 55

Strange that TPS (error 24) didn't come up with the car idling that high

What should i do now and what do the codes mean? and how do I fix it

[Will2003tj]

it sounds very much like the TPS just from the symptoms. Go figure though, my tj through a tps code on the weekend and was jerky / idling high later in the day.

Although today the engine light went off and all seems normal for now.

It is most likely dust / water on the TPS connector or computer connectors. Take the connectors off on both and give them a clean and a spray with wd-40 or another electrical contact improver. Disconnect the battery negative terminal and leave for a minute. This should clear the computer of power and reset some of its memory.

The TPS units are very simple and really i don't understand how they could fail. They are a very simple hall effect sensor. However i have replaced mine anyway for peace of mind. They are much cheaper to get form the states if it comes down to it from somewhere like rockauto.com


PO 132 according to google is an oxygen sensor fault code. Again clean the connectors and reset the computer as above and see what happens... you may be lucky.


Cheers

[Will2003tj]

this is sounding more and more like a dodgy connection to the computer. The fact that you had an error of power supply to the pcm indicates over a bump etc the connection to the computer has wobbled loose and also created other faults linked to the same connector.

[Hunno]

or the battery has been disconnected lately

[SteveC]

Steve - what the guys said all ,all make sense

I agree the TPS could be the problem. While my Jeep is different, I had problem with the TPS, cleaned it and still problem persisted until I replaced it from and never had a problem with it again. Because you hit a bit of mud & water on weekend I suggest a good clean and WD40 is a good idea. I also hit the OS sensor on a trip with an errant stick I suspect which gave me errors too. It had to be replaced at the time