[ludozici]

Hi all -

Yesterday I replaced the thermostat in my '06, MT, 139k, filled system and left it sitting in the drive seemingly happy.

This afternoon I went out to move it and weirdness ensued! At the on position the dash fully lights up, but upon start the dash dies except for the battery light, and the engine, though running, has zero power. Yesterday's coolant refill was messy as the cap wasn't fully seated and threw a significant amount of coolant around, which I immediately rinsed, so I suspect something is wet and unhappy.

I checked for codes, none to be had. I found a single thread on another forum identifying the ECM as the potential culprit, but I'm not ready to jump off that cliff just yet. The battery and IPDM are new, the alternator is original. I'll get under the hood when the flooding here stops, check the battery terminals and output of the alternator, but I thought it would be proactive move to throw this out to the forum in case there's something else I need to look into as well.

Thanks in advance!

 

[Brunnie]

Step 1 - Read battery voltage before doing anything.

 

[ludozici]

Update: went out tonight and fired it up, dash is back on after engine starts, engine revs normally. Checked battery before cranking, 12.4v before startup, after startup 14.5v at the battery.

When I rev the engine, dash goes black and battery light comes on, release the accelerator, battery light goes off and dash returns to normal.

Am I seeing alternator failure or something else?

 

[Jard]

What is battery voltage while reving?

I have seen over voltage many times, when the voltage regulator goes bad, but I have not seen dash lights go out and back on before. This would be caused by a loss of voltage anyways.

I would double check battery and double check IPDM connections. Loose connections can cause a storm of problems.

 

[ludozici]

Thanks Jard, I’ll check revving voltage and connections this morning.

Thanks to you and Brunnie for posting.

 

[RamTest]

Coolant on the alternator belt will cause significant slippage.
The belt and pulleys need to be as clean as you can get them.
Think dishwashing liquid followed by thorough rinsing from the garden hose, or self serve car wash wand.