Test U: Dual Generator Lower Fault Detected (P1148)
PINPOINT TEST U: DUAL GENERATOR LOWER FAULT DETECTED (P1148)Normal Operation
The generator output is determined by the voltage of the A circuit 35 (OG/LB). The A circuit voltage is compared to a set voltage internal to the voltage regulator and the voltage regulator controls the generator field current to maintain the correct generator output. The set voltage varies with temperature and is typically higher in cold temperatures and lower in warm temperatures.
This pinpoint test is intended to diagnose the following:
- Lower generator disconnected
- B+ circuit fusible links
- B+ circuit (lower) open
- A circuit open, short to ground or high resistance
- I circuit open or short to ground
- Lower generator
U1-U4:
U4-U6:
