KSES300

I finally got the ECM out of my car after experiencing two reoccurring error codes. My car won't engage Drive, 2 or 1 but will drive in Reverse. It gets a P0500(shift selector malfunction) code, but only when I accelerate above 3k rpms in drive. I clear that code and I immediately get the P1600(ECM battery malfunction) code. Once I clear it, it comes right back on.

I took the ECM out, dismantled it carefully and looked for any signs of damage, ie. burned spots on the circuit boards, corrosion near capacitors, etc, but I found nothing. It looks brand new. I plugged it back in, started the car and wiggled the wires to see if anything might be loose or show signs of a short....nothing.

Is there a way to test the ECM out of the car? How do I test the cables that plug into it? I just want to be absolutely sure that this unit needs replacing. I'm not a Mechanic by any stretch, so if these are stupid questions indulge me, please.

808mcv20l

It's hard to tell if something electrical is damaged or fried just by looking at it.

I had a bad mirror control module, was bad when I bought the car, and after thorough troubleshooting I bought a used one to test. Sure enough the module was bad.

I opened up the old one and examined the board but could find no signs physically of something damaged/broken.

But I think for your Vintage, the most obvious problems with the ECM were blown capacitors.

They would look expanded, cracked or leaking would be obvious signs.

Other possibles is cracked solder joints on components that also causes issues.