09 Tb 6CYL intermittent start

[Greying]

Sometimes my TB will not start, the radio losses settings etc. I boost it and away it goes. When it does not want to start, I can take the key out of the ignition. Today, I checked the bat voltage, sitting still, nothing on (that I know of) voltage was 12.02 to 12.06. With engine running, 14.2. If I leave the headlights on for 5 minutes, it will not start, What gets me is with the same routine, get up drive to work, park leave work start, it might or might not start.
I am suspecting a faulty battery, it is the original and does not seem to have any reserve. When it goes dead, it will not turn the motor over at all.

I am also curious to know if someone can tell me what part # 25826405 (module) does. It is located on the ground cables right next to the battery box.
Thanks

 

[MAY03LT]

....voltage was 12.02 to 12.06....I am suspecting a faulty battery...

I'm with you on that. Usually I'd suggest a charge/load test but based on the symptoms I'd say it's time to replace it.

I am also curious to know if someone can tell me what part # 25826405 (module) does. It is located on the ground cables right next to the battery box.

The fancy name is the Generator Battery Control Module, although I have seen it referenced as the voltage control module. It monitors and controls the alternator output mode based on inputs from the pcm.

 

[GCTB1289]

Yes definitely time to replace the battery