Touchy check engine light?

[Weichl]

My SMB 2500 check engine light keeps coming on. I had it checked and the mechanic said the diagnostic showed a handful of random codes that don’t check out. He cleared it and said if anything is pulling or “triggering” the battery that might be the issue.
This morning I turned on Espar heater (which was just repaired). Later when I started the van the engine light was on again.
Any idea if these two things could be connected?
Thanks I’m advance. I’m driving cross country and really don’t want to be staring at the light the whole time or paying to have the engine light diagnosed in every town.

[86Scotty]

What vehicle are we talking about, specifically.

Very doubtful the Espar has anything to do with a CEL on the dash unless the CEL was caused by low voltage.

If we're talking about a Sprinter I wish you luck.

[Weichl]

Thanks 86Scotty. We did hit low voltage for about 30 seconds, then started the engine to get it back up. Think that might have done it?

[Weichl]

And yes, it is a Sprinter…

[Fitz]

Do you have a code reader? If so, pass on the codes that are being thrown. If not, you need one…

[Weichl]

I don’t have one but will get one. I was wondering if such a thing existed. Thank you.

[Fitz]

I have had good luck with the Blue Driver, it reads codes and gives a good level of information on them plus it lets you clear codes. There are several references to it showing the output screens in my ongoing build thread. Do a search on Blue Driver on posts with me as the author and you should find them without too much trouble.

[86Scotty]

Originally Posted by Weichl

Thanks 86Scotty. We did hit low voltage for about 30 seconds, then started the engine to get it back up. Think that might have done it?

I don't know. That's what I meant by wishing you luck. I wasn't knocking Sprinters, they are just much more finicky and more electronically complex.

Originally Posted by Fitz

Do you have a code reader? If so, pass on the codes that are being thrown. If not, you need one…

Most definitely. Any OBD2 scanner would be better than nothing, whether bluetooth or not.

[kbeefy]

Separate you house and chassis electrical.


Low(er) voltage on a newer rig will cause and endless string of faults.

[Pntyrmvr]

I have a Blue Driver reporting the PCM voltage on my 1979 Hemi swap. I use a digital voltage readout USB plug in the cigarette lighter for battery voltage. The 2 never match and I suspect a bad battery.

Keep your eye on battery voltage as well as PCM voltage is the moral of the story.

Love the Blue Driver too.