S-10 Codes. No codes from my PCM!

I need help! My “Service Engine Light’ just came on tonight. So I had my local Schucks autoparts store run their scanner on it. My truck showed nothing! No codes at all! Zip, zero, nothing! Not even good codes were present. I took it to two different places and BAM the same result. Nothing! It was like the scanner was dead. They both told me it had to be my PCM.

The truck had just been started 5 minutes prior to this light coming on. My truck is a 1998, S-10, 4cyl, Vortec, 2WD. It has 67k on it. Never had a problem with it. It still runs great and shifts fine (automatic). All the electronics work fine.

2 minutes prior to the light coming on I drove through a six inch deep puddle in the road (Oklahoma and flash floods in the streets). So Happens I was stuck in the lane where there was standing water. This puddle caused a splash and I thought nothing of it. Could it have damaged my PCM? I checked the engine compartment when I got to the auto store, but it looked dry. Guess it could have dried off from the engine heat.

So I have these couple of questions:
1) What could possibly cause my PCM to give me a check engine light AND give no codes at all (scanners appeared to be dead when hooked up) yet still let me run the truck without problems?
2) Could the puddle caused a connection to possibly get wet and interfere with the readings?
3) The gentleman at the second store I went to said that Chevy warranties their cats and PCMs for 8 years or 80k miles. Is this true? I no longer have the warranty booklet that came with my S-10.

Am in a world of troubles. I need my truck to operate correctly for work and family. I can’t sink a bunch of money into it because my wife and I are expecting our first child in 6 weeks! It’s not a good time for this to happen, but when is it ever a good time?

So I am asking to see if someone could please help me understand what might cause this? I am truly perplexed! Any help or guidance would be greatly appreciated!

Thank you!
Mike

Hi Mike, and welcome to the AF forum! We had a similar thing happen to our 99 S10~our check engine light came on...we tried to get a scanner plugged in and it acted completely dead. One of the members suggested replacing the cigar/cigarette lighter fuse...I guess it is the one that powers the computer terminal so the scanner can read the codes. We did that and it worked immediately. We had the Auto Zone read the codes... Of course, they wanted to sell us a new PCM too...I guess thats their job to sell you something you probably don't need.

You might check this fuse; once the codes come up then it will point you to the problem area for the check engine light. The members on this forum are really helpful~amazing what they can diagnose without even seeing the vehicle!

Good Luck!

yep, the cigerette lighter fuse is the one that powers the dlc (data link conncetor) check it and if its popped then the scanner wont communicate, and yes the parts stors attendents are suppose to sell you the most expencive thing possible

THANKS GUYS!!! :p
It was that darn fuse! I ask who would have thunk it?
I ended up changing the fuse a ssuggested and bam it worked!
I am sure glad I broke down and asked. I want the two of you know that I REALLY do appreciate your help! THANK YOU!
Grateful in OK,
Mike