On Board Diagnostics

[Socalerv]

Have a 1990 so I assume I have a OBDI. Is this function defined in any of the manuals?

I have read strings explaining repairs of the INF Rest that requires wires to be jumped to receive codes and reset. So that leads me to the question what information is available from the OBDI?

I asked a friend to bring his scanner over and plug it in, he told me he could not read it. If there is valuable information stored here what type of scanner should I buy and what do you think of his scanner not working on my car.

I come from the old gas + spark = engine runs days so electronics will be a challenge for awhile.

[John Boothby]

If you have a INF REST light it is probably a bad ground on an air bag sensor. There are a couple of "SIR" techtips found under Maintenance on the home page. They also explain how to extract codes and clear codes using just a simple ground wire.

INF REST is "Inflatable Restraint" and found in the Service Manual in section 9J.

[Socalerv]

Is there a reason his hand held scanner would not work on my car, something obvious I should know?

[Socalerv]

Would this scanner work on my 90?

Sears Tech I scanner: http://www.sears.com/shc/s/p_10153_12605_SPM6027015902P?blockNo=1&blockType=G1&prdNo=1&i_cntr=1320014878924

[tomtom72]

The Sears add doesn't mention that it comes with OBDI software, so I would assume that scanner only has "Generic" OBDII Global DTC translations. Further, that scanner may not give much in the way of real time data as in scanning any car with the motor running, I could be wrong with that thought.

The trick with scanners is the software package. The trick to our cars, which are OBDI, is to have the correct licensed software with the scan tool so that the scanner is enabled to communicate with the various modules. For example I have an antique snap-on MT2500 unit with software for GM engine control systems for my model yr plus a troubleshooter software, and an ABS software package.

Those three software cartridges allow me to "see" live data with the motor running, "see" any ECM stored DTC's and clear them, and "see" what's up with my ABS system. Notice I said ECM stored DTC's.....because I don't have the software for the CCM I can't read anything stored in it.

The software is the expensive part of any scan tool because to get the right read outs you have to have licensed software. Another issue are functional tests done thru the scan tool. If you're lucky enough to find a Vertronix/Kent-More TECH1 or TECH1A with all the software for our model yr ZR-1 then you can do many of the "live" functional tests that are outlined in the 6E section of our FSM. Other brand scanners may or may not be able to do all of those tests it just depends on how much licensing money they were willing to part with.

:cheers:
Tom