FERM and any other Jeep guys......

[Seacrets]

Typically, the check engine light is set to come on after a certain mileage so you will take it to a dealer for an emissions checkout. There is probably nothing wrong with your Jeep.

[tsubaki]

I had 2 vehicles that did that at exactly certain miles, on one of them the EGR light would come on at exact miles.
After determining there were no problems, I just found the reset, reset them and off for another 10-20,000 miles.
This shouldn't be the case with this one.
Resetting one (now) without a code reader is as simple as disconnecting the battery for 12-24 hours. But the problem will show up again in a week or two if uncorrected.
Allright FERM, get over here!!

[THEFERMANATOR]

Originally Posted by Seacrets

Typically, the check engine light is set to come on after a certain mileage so you will take it to a dealer for an emissions checkout. There is probably nothing wrong with your Jeep.

That is not the case here, I can assure you. After 92 no chrysler product used a maintence required system on them, and OBDII I believe is mandated NOT to have one. Go to AUTOZONE, they'll check it for you for free. On a 99 you may still be able to get the codes by the old key switch on off on off on off on(some take 3 on's and some take 4) self diagnostic in 2 second intervals and on the last on leave it there. On a 99 the odometer should read out the CHRYSLER HEX code, if it does I got the book to tell you what they are(or you can look them up on line as well). I don't think a 99 TJ will have an LDP, so a loose gas cap is probably not it. If the JEEP is running well with just a check engine light(after a cracked manifold), then chances are that it will be a cat efficiency code or downstream O2 sensor performance code. Only way to know for certain is to get the codes and go from there. CHRYSLER's OBDII is normally pretty spot on, so codes are normally a pretty reliable diagnostic tool.

[tsubaki]

Our 94 Caravan had the dash diagnostic.
I tried it with a couple of other newer vehicles and they just sat there, but then again, I haven't gotten books on the other vehicles.
Oh, the loose gas cap-check engine light, is the number one thing on the Pacifica.

[C YENSEN]

so FERM, your telling me if i turn the key on and off 3 or 4 times the dash will tell me the code for the problem?

[THEFERMANATOR]

Originally Posted by C YENSEN

so FERM, your telling me if i turn the key on and off 3 or 4 times the dash will tell me the code for the problem?

You can try it and see. I know my 97 did, and some of the 99's did as well. It only takes a minute to try and see. The main thing to watch for is the check engine light to flash, but the odometer should also give a digital read-out of the actual number if it will do it. I know on the trucks 99 was hit or miss wether it would do it or not. So your WRANGLER may be able to.

[C YENSEN]

so ON and OFF....wait two seconds....on and off.....2 seconds.....on and off.....2 seconds......on then see if the check engine light blinks and look for a code number on the odometer??? think i got it.....give me 5 minutes and i will be back.....

[C YENSEN]

well just tried it several ways 3 ons and then 4 ons, and no luck.....

did i do it right? do i have to start it or just turn the key on and off?

[tsubaki]

If that don't work, do it all within 5 seconds.
The book on the Caravan says 1989-95 just turn the key on but it was published in 1996 and may include newer models.
By the way, you're not cranking it up, just turning it on till the dash lights come on.

[THEFERMANATOR]

2000 or 2001 on would have the check engine light from the loose gas cap. CHRYSLER Called it the LEAK DETECTION PUMP(LDP), and it was a PITA! It would often times throw a check engine light just for the heck of it, CHRYSLER programmed the wrong variables into it in it's first year, and it would set the light in under 20 seconds, well it takes upwards of 2 minutes to pull the tank down under a vacuum. I HATED the LDP with a passion, unfortunately though I was the only one in the shop that was able to efficiently use the LDP diagnostic machine.