Discussion in 'Gen 1 & 2 - Electronics & Audio' started by plumber, Apr 14, 2019.
I have a 1993 SHO. Should CEL be on with KOEO and off with KOER. I also am unable to pull codes.
if you just turn the key to "on" they check engine light will stay illuminated. if it does not, that suggests the bulb is burned out.
if you connect the jumper as shown on the various pages that show you how to pull codes on obd1, then the check engine light will flash. if the light is burned out, you may connect a 12V light, and that light will flash out the codes as well. see:
Thank you for responding. My light does come on with key on but should it go off when trying to start. I'm trying to find out if that could mean a bad PCM. Because I've tried the jumper method and obd1 scanner and I can't pull any codes and the light does not flash. I tried with test light and same result. Thank you Plumber
It should at least return a 111 if there are truly no codes. Maybe post pics of the connector, let's see if it might be damaged at all. OBDI scanners are notorious for their uselessness.
KOEO should make the CE light flash the codes. KOER, the light will flash occasionally. CE light comes on with ignition on, off when started. Sounds like you've pulled codes before, but just in case:
Code meanings are there as well.
Hello. Yes a month ago I was able to check codes and the cel would flash. Now I can't so I'm worried something happened to my pcm. Are there other reasons for not being able to pull codes ? Thank you Plumber
Are you using a paper clip or code reader?
Hello. I tried a code reader first and nothing. Then I made jumper wire with 1/4 spade and still get nothing. Thanks Plumber
ATX or MTX?
Whichever, here are the relevant diagrams for both showing the wiring to the 'VIP Data Link Connector' for both. For a 94, not a 93.
Thankyou . I will try to check out wiring later. If you have any ideas let me know. Thanks again Plumber
When I probe DLC with test light to battery I get 12v on neg and pos post. Is that normal. The test light just stays on no blinking. Plumber
I later tried the 5v ref test on tps and only get 1.95 v.
When I connect a test light from DLC connector to battery it lights on either neg or pos post. Is that right?
Don't know. Do you have a voltmeter?
So use that on the battery.
What readings should I get?
12v engine off, 13.5v engine on.
thanks. Now is that 12v on touching test light to either post? Plumber
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