Check Engine Light

Hi : I have a 2001 Jimmy 2dr. 4wd(auto 4wd). Recently the Service Engine Soon Light came on , I took it to auto zone to have the codes checked. But my car wouldn't power the tester? So I couldn't get any codes. I checked all the fuses all are/were good. Any thoughts? :banghead:

I have that re-occuring problem. Dealer said its some type of sensor to exhust fumes form gas tank or fumes from exhust. This sensor was replaced and the engine light still comes on intermittently, Does no harm to vehicle when light is on. Also I heard that it can be a faulty gas cap?? I've given up. I just leave the engine on, It goes out when it wants to.

Hi : I have a 2001 Jimmy 2dr. 4wd(auto 4wd). Recently the Service Engine Soon Light came on , I took it to auto zone to have the codes checked. But my car wouldn't power the tester? So I couldn't get any codes. I checked all the fuses all are/were good. Any thoughts? :banghead:

spend a few extra bucks and have a gm dealership shop put the megadiagnostic monster on it, and i think down here, it's 90 bucks usd, but it will tell you way more than you want to know and they will even give you a print out and explain what's up, or go to a good mechanic that has a good rep and if he has an average sized shop, he will do it, personally, i don't take mechanical advice from someone who wants to sell me autoparts, no offense, most are good guys, but these days, the parts guy is not usually a mechanic, he is a retail sales person.
the not powering the code tester is odd, maybe the diagnostic port has a bent/pushed/broken pin???

SES light on for no reason?

Try this: Take your jimmy to a local mechanic and have him reset the SES light for free (or unplug the battery for 24hours to reset the internal computer).

Unscrew your gas cap and screw it back on, make sure you turn it long enough to hear three clicks and do this everytime you fill up.

I believe this is caused by sensor detecting a fuel fumes leak from the owner not tightening the gas cap or GM's cheaply made half-@$$ed gas cap.

SES light on for no reason?

Try this: Take your jimmy to a local mechanic and have him reset the SES light for free (or unplug the battery for 24hours to reset the internal computer).

Unscrew your gas cap and screw it back on, make sure you turn it long enough to hear three clicks and do this everytime you fill up.

I believe this is caused by sensor detecting a fuel fumes leak from the owner not tightening the gas cap or GM's cheaply made half-@$$ed gas cap.

Okay... You've now ressurected 2 almost 2 month old dead threads. Why? I see that you're new, but try watching the dates..

Second, it only takes about 15 mins, 1/2 hour max to reset a computer by disconnecting the battery. (Less if you cross the negative and positive battery cables (while disconnected from the battery) so that all the capaictors drain in less than a second)

Third, If you read his post, the ALDL wasn't powering up the scanner, so there are issues there that need to be addressed.

Fourth, Resetting the code without finding out what it is first is just plain bad advice to give to anyone. Yes, the SES light could mean the evap system pressure isn't right (hence tightening your gas cap). Unfortunatly it could also mean literally 800 other things from a bad 02 sensor to bottom end damage, to transmission or BCM problems. Again, telling someone to reset their ECM just to get the light out without finding what the problem is that's causing the SES light in the 1st place is just plain bad.