Attention: TDR Forum Junkies 
I pulled the drivers side battery looking for the battery temp sensor. There was no sensor, so I pulled the passenger side battery again no sensor. In the passenger side tray there is a round hole that looks about the right size for sensor. Called my dealer and was told the battery temp sensor is inside the PCM. I just can't see how that would work, surely the dealer is mistaken. Called 2 other dealers neither of them wanted to talk about anything other than make an appointment for them to check it out.
A little back ground to my search for the battery temp sensor:
Last week while driving up I-35 in Mo at around midnight my headlights flash dim and bright. Mini Max shows voltage was dropping(12ish), pulled over and problem magically went away with voltage returning to 14+. Popped the hood to look, no bad sounds and belt appeared good. Drove a few more miles trying to make it to the next town. the problem came back about a mile before town. Stopped and voltage returned to normal. Decided it was best to stop for the night then check it out in the daylight. Next morning truck started fine but was not charging as it should. Went to parts store had batteries and alternator tested.
Found codes
P0562 system voltage low
P2503 charging system voltage low
P063D generator voltage sense high
P2504 charging system voltage high
Batteries are good, alternator had a bad clutch. Before installing the new(rebuilt) 160 amp alternator, had the parts guy test it, tested good. Installed replacement alternator, it would not output any voltage. Tested the field terminal connector, one wire was broken at the plug, installed new plug and no joy. proceeded to clean all battery connections and ohm the crossover cable(.1) all good. Also checked continuity of cable from alternator to battery, it is good. Have not found a fusible link. fuses are all good. Checked codes again now show P0626 generator field terminal circuit high. At that point decided to trailer the truck back home. Today I took the truck in to my cousins shop he has a Snapon scanner, we found that the battery temp sensor is maxed at 5 volts equaling 189.5 F. From what I understand is the PMC will not charge since it believes the batteries are to hot.
If I get time tomorrow the plan is to pull both battery trays in search of the battery temp sensor.
Anyone have suggestions or a similar charging issue ?
Thanks in advance
A little back ground to my search for the battery temp sensor:
Last week while driving up I-35 in Mo at around midnight my headlights flash dim and bright. Mini Max shows voltage was dropping(12ish), pulled over and problem magically went away with voltage returning to 14+. Popped the hood to look, no bad sounds and belt appeared good. Drove a few more miles trying to make it to the next town. the problem came back about a mile before town. Stopped and voltage returned to normal. Decided it was best to stop for the night then check it out in the daylight. Next morning truck started fine but was not charging as it should. Went to parts store had batteries and alternator tested.
Found codes
P0562 system voltage low
P2503 charging system voltage low
P063D generator voltage sense high
P2504 charging system voltage high
Batteries are good, alternator had a bad clutch. Before installing the new(rebuilt) 160 amp alternator, had the parts guy test it, tested good. Installed replacement alternator, it would not output any voltage. Tested the field terminal connector, one wire was broken at the plug, installed new plug and no joy. proceeded to clean all battery connections and ohm the crossover cable(.1) all good. Also checked continuity of cable from alternator to battery, it is good. Have not found a fusible link. fuses are all good. Checked codes again now show P0626 generator field terminal circuit high. At that point decided to trailer the truck back home. Today I took the truck in to my cousins shop he has a Snapon scanner, we found that the battery temp sensor is maxed at 5 volts equaling 189.5 F. From what I understand is the PMC will not charge since it believes the batteries are to hot.
If I get time tomorrow the plan is to pull both battery trays in search of the battery temp sensor.
Anyone have suggestions or a similar charging issue ?
Thanks in advance
