Has anyone purchased a scan tool to check engine codes? Do you have a preference on which one to buy? Your assistance is greatly appreciated.

If i were you i would get the one snap on sells actually blue point..from Canobd2.. since you have a 88 your gonna need OBD1 and this scanner will do obd1/2 i paid 230 for it. well worth it.!! http://www.canobd2.com/Products/Tool...D89A9363E13C77

on alot of the obd1 systems you can check your codes with a paper clip by jumping a conector not sure how to do it on the xjs but on my mustang you can jump the 2 plug ports and then ur check engine light will flash a certain number of times to give you codes then you can post your code numbers and we can help you find the issue

Computer codes. It tells which cavities to jump in the terminal for code retrieval on required years.

its called a KOER test...You start the test with a paper clip and can use a test light or the check engine light to counts the flashes.

Hold it, stop, whoa, and wait a minute!

If he's got an 88, it's not RPT NOT OBD!

The Snap-On MT2500 will work, I believe Mac and Matco make readers that will work, and the Chrysler DRBII will work.

However, that being said, note that there are no codes given with the 1987-1990 XJ/MJ w/AMC gasoline engine! The system (RENIX) is "pre-OBD," and doesn't conform to the OBD-I standard. I do not believe the Renault Diesel was OBD-controlled either, and the only "early" (pre-1991) XJ/MJs that were OBD-controlled were 1984-1986 XJ/MJ w/GM 2.8L V6 (they used GM OBD-I electronics.)

Most troubleshooting to be done on RENIX can be done with a decent DMM - you can get the RENIX FI manual at Pirates of the Rubicon, and I believe someone upped it to my RENIXPower group as well (groups.yahoo.com/group/RENIXPower - it's a sort of "clearinghouse" of RENIX information that I kicked open a while ago. We're still accumulating...)

Again, none of the "cheap" (read: "readily available") OBD scanners will work with RENIX, simply because it's not an OBD-compliant system!

(Trust me on this, I've had five RENIX XJs to date, and I've solved problems on quite a few more...)

Thank you all for the replies. MY BAD, I did leave out some crucial information about what I have. I am retiring the 1988 Cherokee, I now have a 1991 4.0L Cherokee. Huge difference, thank you 5-90 for the good catch. I need to update my profile. I was reading in a manual where you can cycle the key on-off, on-off, on and the check engine light will flash. My main concern is getting the Maintenance light to go off.
Thanks again to all!
Jeff

I know that advanced auto parts lets you borrow scanners for free.. i used one the other day to clear one of my codes after i fixed it.

The EMISS MAINT lamp is different from the CEL/MIL, and it is usually triggered by a mechanical timer. Getting that lamp to go out is easy - find the timer underdash somewhere and remove it.

Alternatively, remove the bulb.

The EMISS MAINT lamp has nothing to do with OBD, and removal of it therefore does not constitute a problem. As I said,it's triggered by a timer, and the timer module is a one-shot disposable deal.

if you just want to clear it after a fix try disconnecting the negative terminal on the battery for about an hour if its still not got to autozone and have them clear it for free

1) That won't work for the EMISS MAINT lamp, unless there's something come up I haven't been informed of.

2) OBD-II usually needs to be cleared in software (using a code reader - and it logs the clearance,) while OBD-I is much easier. Disconnect the battery leads and touch them together for ten seconds. That drains the internal caps for the memory and resets the RAM to zero. Easy!

I have an Auto Xray I got from Summit Racing for about $200. It does OBDI and OBDII, all the major brands. It is also upgradable with software packs to reprogram the computer chip.

it works on gm but any who take that shiot to autozone and theyll clear it!!