mikekozura

My son's Silverado won't fear the modules at the garage for the emissions test. We did all the go but a 100 miles on it thing. PCU or wire ????

ToooTall1

Check your cigarette lighter fuse

cleveland63b

does the scantool power up?

mikekozura

Yes our hand held scanner reads. And the OBDII fuse is good.

cleveland63b

so it powers up but doesn't read the ECM? Do you have access to any other modules or a different scanner?

mikekozura

Our hand held scanner reads but when I take it to the garage for emissions inspection it doesn't read the modules it needs for the test. I guess the ECU is not storing them

cleveland63b

I don't really understand what you're getting at I guess. My guess is you need to try a higher end scanner

maddog0324

I'm having a similar problem with my '04 Silverado LT 5.3L. The I/M monitors will reset after reading with a code scanner. Someone suggested that the nonvolatile memory isn't retaining the information for the I/M monitors. Has anyone heard of this?

maddog0324

Update:
It turns out that the ECM was bad