Check engine light.

[jon L]

My check engine light come on and off whenever it feels like.

I know why, I would just like to keep it off.

My air temp sender has been moved because of my custom air 

intake. When I unplug the sensor the light stays on all the time.

When it is plugged in it comes on and off whenever it feels like.

Is there a way to keep if off?

[2seater]

My only suggestion would be to try a different sensor. I have relocated my sensor in various locations, including in the side of the throttle body and have never had a check engine light because of it. Do you get a code for that sensor?

[Ronnie]

I have a cold air intake for my car but I don't have it installed right now.  I never got a code or a SES light because of it.  . You can see the MAT sensor sticking out on the bottom of the chrome pipe in the photo below.

 

I think as 2seaer said, checking for codes is the key to figuring out what is causing the problem.  If the SES light is coming on it should set a code in history. Probably a code E023 (too cold) or E025. (too hot). I'm betting you have a code E023 because the FSM leads me to believe that would be the default code if you have a bad sensor or a bad connection in the wires going to it.

 

 

[jon L]

OK, I checked the codes.

And I got

Eo23

Eo25

Eo61 ?

But they all  History.

The check engine light comes on when I start and stays on until it feels

like going off, Later it will come on and of whenever.

Any Ideas.

I'[m not worried about it , it is just bothersome.

Jon..

[Ronnie]

E023 & 25 are caused by the MAT Sensor or wiring. Have you tried another sensor?

 

The E061 is probably a E051 (ECM PROM error) Might be caused by yours being reprogrammed for the supercharger?  I don't know.

[jon L]

Thanks for the reply Ronnie.

Th MAT Sensor is new and all of the codes are History..

I just want to turn off this light.

I guess the only way is with tape.

Jon

[Ronnie]

A lot of times a code only showing in history indicates there is a bad connection to the sensor because it loses a signal just long enough to set the code and turn the light on and then it goes away.  You can can clear the codes to get rid of the light but if there is a bad connection it will come back.  You could tell what's causing the codes if you know how to access ED23 in diagnostics and watch what the MAT sensor is doing while driving to see if it goes out of range.  Without you having a CRT I can't tell you how to do that.  Maybe 2seater who has a '90 can tell you how to do it.

 

This will sound crazy but If I were in your shoes here is what I would do.    Assuming you have the old sensor, put the old one back in the intake to plug the hole but don't attach the wire harness.    Then plug the new sensor into the harness and wrap the sensor and connector tightly in a shop towel.    Put a few rubber bands around the towel so the sensor and connector can't move around.     Lay the sensor wrapped securely in the towel somewhere on the fenderwell so it won't move around with the engine.  Clear the codes and drive around to see if the light comes back on.  If it comes back on check the codes and see what you've got.  If it doesn't come on you probably have a bad connection or break in the wires where the sensor connects to the harness.

 

Or as you say... you can  put a piece of tape over the light and skip all the troubleshooting.  That would be a lot easier but that would take all the fun out of owning a Reatta. ?

[jon L]

Thanks again Ronnie.  I am going to try what you said and see what happens.

And your right about taking the fun out of owing a Reatta.

[jon L]

Can anyone define these ECM codes for me

023

024

025

033

043 c

052

061

Any help would be great.

Also where can I get a copy of ALL the ECM codes?

Jon.

Edited September 12, 2019 by jon L

[Ronnie]

You can click on "Diagnostics" in the menu at the top of this page and you will see a drop-down menu with a list of all the ABS, BCM and ECM code charts as well as some other diagnostic items that are here on ROJ.

 

Here is the ECM code chart.  As far as I know it is a complete list for an '88-89 model.  The '90 models might have more codes than the earlier models.  I'm almost certain a '91 model will be different.  If you need any help figuring out the codes you posted let me know.

 

Click on the chart below to see a larger chart that can be printed.

[2seater]

I have looked around a bit online as well and I found conflicting information for GM OBD1 codes but 061 appears in more than one place as referring to the O2 sensor being sluggish/contaminated. The other that had multiple references is 033 = MAF. One reference to 052 being CALPAK fault. Part of the issue is OBD1 can be manufacturer and even car model specific so it may vary even between model years for the same vehicle. I will see if I can fill in the missing codes from my FSM for a '90.

[2seater]

I did look in my '90 FSM and the three missing codes, 033, 052 and 061, do not appear there either?? I think I may have seen E061 myself at some point but it isn't in my manual.

[jon L]

OK, I'm stumped.  Followed Ronies suggestion, nothing. Light stays on.

Checked wires back to firewall, all good. Light stays on

Changed MAF with three other good ones, light stays on.

Cleared codes. light stays on.

 

Anyone?

[Ronnie]

I'm a little stumped at this point too. You could dry disconnecting the ECM and spraying all the connections with contact cleaner to see if that helps. Or try another ECM if you have one.  Seems like I remember someone on the forums was getting odd codes popping up and a different ECM fixed it.