No check engine light in car, but i know codes are present.

[TooGoode]

So im working on a buddys 87 supra and i know he has codes as there is one knock sensor not connected, but there is no cel. even when i first turn the car on, the light doesn't come on. i replaced the bulb and still nothing. my question is this: is there a way i could maybe attach a 12v light to the diag port to blink so i can get what codes i have? i just want to know what all codes i have after the rebuild. thanks

 

[gaboonviper85]

Very few codes make the light come on...what happens when you turn the key all the way on (without cranking)...does the light come on then? When you jump the diagnostic does the light blink! I'm confused

 

[supra90turbo]

Did you actually attempt to pull codes or are you only going off the light?

There probably are codes present but not setting the light.

Pull codes, see what happens.

 

[Clint]

Did you actually attempt to pull codes or are you only going off the light?

There probably are codes present but not setting the light.

Pull codes, see what happens.

x2

 

[StrikeIS]

Have you tried jumping the terms with a paper clip on the diog plug.

 

[TooGoode]

he has no cel period. it never turns on. i know for a fact he has codes. im not worried about that though, i just want to know if there is a way to pull them as if the cluster didn't exist

 

[gaboonviper85]

he has no cel period. it never turns on. i know for a fact he has codes. im not worried about that though, i just want to know if there is a way to pull them as if the cluster didn't exist

Volt meter to the check engine light wires....count the fluctuations?