Quote:
Originally Posted by country dad
If the mega fuse is bad, would the hole truck not work...
|
schematic shows 175 amp fuse as the only connection from alternator output to battery. The battery cable goes to the power bus in the distribution block also. So that would indicate ther would still be power to the rest of the truck. Here is the tree for t-shooting from the service DVD:
The Charging System Warning Indicator is ON with the Engine Running (The Battery Voltage Does Not Increase) 4.0L possible sources:
- A Circuit 36 (Y/W).
- A Circuit mini-fuse.
- B+ Circuit 38 (BK/O).
- B+ fuse link.
- I Circuit 904 (LG/R)
- Voltage regulator.
- Generator
1: Check A circuit mini Fuse 24 (15A) in power distribution box.
OK -go to 2
2:Measure the voltage between the B+ terminal on the generator, Circuit 38 (BK/O).
- Is the voltage equal to battery positive voltage (B+)?
Yes
GO to
A3 .
No
REPAIR Circuit 38 (BK/O). TEST the system for normal operation.
3:
Measure the voltage between generator connector Pin C-121-A Circuit 36 (Y/W) and ground.
|
| - Is the voltage equal to battery positive voltage (B+)?
Yes GO to A4 .
No REPAIR Circuit 36 (Y/W). TEST the system for normal operation.
|
4: NOTE: The voltage regulator (VR) (10316) must be connected to the wiring harness for this test.
- Measure the voltage between the generator I-terminal, Circuit 904 (LG/R) and ground.
- Is the voltage greater than 1 volt?
Yes GO to
A5 .
No REPAIR Circuit 904 (LG/R) for an open or short. TEST the system for normal operation.
5:
A5 CHECK THE GENERATOR OUTPUT
With the engine running, ground the F pin on the generator/regulator.
|
| - Does the battery voltage increase and the charging system warning indicator turn off?
Yes REPLACE the voltage regulator. TEST the system for normal operation.
No REPLACE the generator (GEN) (10300). TEST the system for normal operation.
|
