Pulling codes question

[DennisG01]

Just a few quick questions:

1: Can a code be pulled after the SES light goes off? There has been a few times when the light comes on after an incident (like the starting problem I talked about) but after an hour or so of driving, it goes off.

2: I see a lot of you talking about pulling codes, what are you using to do that? Is it something a non-mechanic can use? Expensive? (my thought is that it might help diagnose a problem that won't replicate when I take it into the garage if I can get the code right away.)

As always, thanks for the excellent advice!!!! smile.gif

[JohnC]

Most codes are stored in a history file. There are a few that are not, and they need to be read while they're present. The '98 trucks require a code reader. Many large parts stores will read the codes for you.

[Dave C]

I bought an interface that hooks up to my PC (laptop or desktop). It cost $88 and the software is free. You can download the software first and play around with it in semulation mode then buy the interface if you like. Here's the web site http://obddiagnostics.com/ . It has worked fine for me. :D

Dave

[ucdavis]

IIRC codes come in two flavors, Current & History. Code is current if failure condition occurred & non-failure condition has not persisted sufficiently long enough to meet the spec for clearing the code or relegating it to History. Some codes also set "Snapshot Data" so you can retreive the engine running parameters @ the time of the failure.
E.g. a code may set due to existence of specified conditions (e.g. out of spec reading while enigne temp >170), and then toll in memory till specified in-spec condition persists (e.g. 40 consecutive starts w/out the condition) @ which time it clears.
If you get the code read shortly after the SES lght comes on you should get it; most don't go away real quick according to the Helm manual.