Can anyone think of a reason why the Check Engine Light will not reset or show any meaningful codes? Have tried all manner of methods to clear it but no joy, and no scanner will connect either. The 'key trick' shows nothing, but if I press the ODO button and turn the key on and off, I get a 2.3 showing - is this a valid code or just a software version?

Thank you!

 

Try this. Scroll down and use the directions for the '98 + models.>Computer codes

And Welcome to CF.

 

Have you also tried disconnecting the battery and grounding out the positive lead while disconnected? just a thought...Tj

 

I believe it is a certain code. I know if it has something to do with a fuel leak or something about an exhaust leak they usually stay on. Is it running rough at all?

 

Why not just take it too the parts store and have it checked? Save yourself the guess work and then you can get right to fixing the problem. Why wont a scanner connect? Do you mean a scanner wont read or what?

 

Yep done all that. No codes are being reported except as already stated, but not even sure thats a valid code; it is in the list, but the display is reading 2.3, not 23

And thank you!

Yep and every other variation of that there could be! Still it stays on.

Code 23 is related to the air temp sensor and I wouldn't say it was running rough, but its not pulling very well.

The mechanic has tried 4 different OBDII scanners, and I have seen him try his - it just will not communicate with the port and extract any codes. Unfortunately here in the UK we can't just take it to a parts store and have them have a look, not that I think they would be successful anyway.

Here is my original thread, with the full list of woes: https://www.cherokeeforum.com/f2/coo...-issues-71705/

I appreciate a lot of you guys won't be familiar with the 2.5TD but any other thoughts or advice would be hugely appreciated!

 

I know this wont be much help but I wonder if there is something wrong with your computer. If a scanner can not connect with it then I would think the computer was at fault. Obviously the light will not go away until the problem is fixed. The air temp sensor is located on the intake manifold. You should be able to easily pull that and replace with a new one. If that is what the code is calling for then just pull the old one and replace.

 

I thought OBD-II codes started with the letter P followed by a 4 digit number (P????).

 

I think that is only if it is pulled on a reader. He is pulling the code on dash probably from the odometer. It will just read a number. This trick does not work on the 01's but I sure wish it did.

 

Sorry, I just noticed you have the 2.5L TD and you're in the UK. That might require a special way to check the codes, and/or a different set of codes entirely. Maybe you'd get a better response in the "International" Section asking for assistance? >https://www.cherokeeforum.com/f64/
It's worth a try, as there's not many 2.5 TD's over here.

 

Thanks for that suggestion but one thing I have been able to establish is that OBDII is an international standard so the codes should be the same both sides of the pond!

 

That's good to know.

 

So does anyone have an opinion on why the CEL would stay on, without any codes or ability to reset? Any ideas would be great!