P1500

Generator Circuit:

CIRCUIT OPERATION
- The ECM (terminal 52) or PCM (terminal 54) apply a battery positive voltage into the generator FR terminal 4 via resistance inside the unit.

TECHNICAL DESCRIPTION
- when the generator field coils are controlled, the generator FR terminal inputs signal to the ECM or PCM .
- The ECM or PCM detects the generator output with the input signal, and controls the idle air control motor according to the generator output.

DTC SET CONDITIONS

Check Conditions
- Engine speed is higher than 50 r/min.

Judgement Criteria
- Input voltage from the generator FR terminal has continued to be approximately battery positive voltage for 20 seconds.

TROUBLESHOOTING HINTS
The most likely causes for this code to be set area:
- Open circuit in generator FR terminal circuit.
- ECM failed.
- PCM failed.

DIAGNOSIS

STEP 1. Check the circuit at generator connector B-45.
1. Disconnect connector B-45 and measure at the harness side.
2. Turn the ignition switch to "ON" position.
3. Measure voltage between terminal 4 and ground.
- Voltage should be between 4.8 and 5.2 volts.

4. Turn the ignition switch to "LOCK" (OFF) position. If within the specification, go to Step 2.

If not within the specification, check intermediate connector B-13 and repair or replace as required.
Refer to Harness Connector Inspection. Then go to Step 6.

If intermediate connector B-13 is in good condition, go to Step 4.

STEP 2. Check harness connector B-45 at the generator for damage.
If harness connector B-45 is not damage, go to Step 3.

If harness connector B-45 is damaged, repair or replace it.
Refer to Harness Connector Inspection. Then go to Step 6.

STEP 3. Check the voltage at intermediate connector B-13.
When the following conditions are satisfied, measure the voltage between terminal number 3 of intermediate connector B-13 and ground. Do not disconnect the connector during this measurement.
a. Engine: Warm at idle
b. Radiator fan: stopped
c. Headlight switch: OFF -> ON
d. Rear defogger switch: OFF -> ON
e. Stoplight switch: OFF -> ON
- Voltage drops.

If the voltage drops, the malfunction is intermittent.
Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope With Intermittent Malfunction.
If the voltage does not drop, replace the generator. Then go to Step 6.

STEP 4. Check harness connector C-58 at the ECM or harness connector C-55 at the PCM for damage.
If harness connector C-58 or C-55 is not damaged, go to Step 5.

If harness connector C-58 or C-55 is damaged, repair or replace it. Refer to Harness Connector Inspection. Then go to Step 6.

STEP 5. Check harness wire between generator connector B-45 and ECM connector C-58 or PCM connector C-55 .
If the wire between generator connector B-45 and ECM connector C-58 or PCM connector C-55 is not damaged, replace the ECM or PCM. Then go to Step 6.

If the wire between generator connector B-45 and ECM connector C-58 or PCM connector C-55 is damaged, repair it. Then go to Step 6.

STEP 6. Test the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern. Refer to Procedure 6 - Other Monitor.
2. Read the diagnostic trouble code, and confirm that diagnostic trouble code P1500 does not reset.