Well i have spent the last 6 hours searching the forums and wrenching on the truck and i have managed to get no where Heres the summary of whats going on;
Over the weekend i lost charge on the alternator and had a friend bring me a new one out and changed it, seemed to be charging fine and the truck sat. Drove the truck a couple days later and all seemed okay, but about an hour into the drive my Check engine light came on, and voltage was sitting around 12 on the dash. The tach also quit working ( but its been fussy lately, working sometimes and not others but now it seems to be out permanently )
Ran the DTC code and it was a 41 - "Generator Field Not Switching Properly"
Here's what ive done so far this morning.
-Cleaned, checked resistance, dialectric greased all connections on Alt and Batt's.
-Re-charged Batts over night, tested OK
-Gapped the ESS, and even took one off a running parts truck to test with still no tach, but with the truck running the CHECK ENGINE LIGHT goes off when i unplug the ESS, and i have 5v and 8v on two of the harness connectors going into the ESS plug. And the CHECK ENGINE light will come back on when i plug back in the ESS.
Now im no wiring expert, i actually hate it for crap like this but on the alternator i also tested voltage at the BATT supply wire and its the same as the batteries, and resistance checked ok also.
When the truck is running the lower connection on the field terminal has 12v, and the top has nothing. Is the top connection on the field terminal supposed to have some sort of power while running? I tested continuity between that terminal and the PCM and its fine but other than that im not sure what else im looking for. :confused013:
Is there a way to "test" the alternator in the truck without any fancy tools? Its a brand new( not reman ) alternator so i dont really want to bring it back to the store and get it tested if it can be done in the truck by triggering it somehow to charge.
Sorry for the long post, just trying to cover everything i have tried to save you guys time on helping me.
Over the weekend i lost charge on the alternator and had a friend bring me a new one out and changed it, seemed to be charging fine and the truck sat. Drove the truck a couple days later and all seemed okay, but about an hour into the drive my Check engine light came on, and voltage was sitting around 12 on the dash. The tach also quit working ( but its been fussy lately, working sometimes and not others but now it seems to be out permanently )
Ran the DTC code and it was a 41 - "Generator Field Not Switching Properly"
Here's what ive done so far this morning.
-Cleaned, checked resistance, dialectric greased all connections on Alt and Batt's.
-Re-charged Batts over night, tested OK
-Gapped the ESS, and even took one off a running parts truck to test with still no tach, but with the truck running the CHECK ENGINE LIGHT goes off when i unplug the ESS, and i have 5v and 8v on two of the harness connectors going into the ESS plug. And the CHECK ENGINE light will come back on when i plug back in the ESS.
Now im no wiring expert, i actually hate it for crap like this but on the alternator i also tested voltage at the BATT supply wire and its the same as the batteries, and resistance checked ok also.
When the truck is running the lower connection on the field terminal has 12v, and the top has nothing. Is the top connection on the field terminal supposed to have some sort of power while running? I tested continuity between that terminal and the PCM and its fine but other than that im not sure what else im looking for. :confused013:
Is there a way to "test" the alternator in the truck without any fancy tools? Its a brand new( not reman ) alternator so i dont really want to bring it back to the store and get it tested if it can be done in the truck by triggering it somehow to charge.
Sorry for the long post, just trying to cover everything i have tried to save you guys time on helping me.