Test Procedure
- AN1 VERIFY CORRECT PTO OPERATION
- Ignition OFF.
- Disconnect the PTO system or auxiliary idle control.
- Ignition ON, engine OFF.
- Carry out the PCM self-tests.
Is DTC P1502 present?
Yes No GO to AN2. REFER to the Owner's Literature provided with the PTO system or auxiliary idle control to verify correct operating procedures, entry conditions, and diagnostic information. - AN2 CHECK THE PTO INPUT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- PCM connector disconnected.
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) PCM Connector, Harness Side (-) PTO Ground Is any voltage indicated?
Yes No REPAIR the short circuit to PWR. CLEAR the DTCs. REPEAT the self-test. CLEAR the DTCs. REPEAT the self-test. If DTC P1502 is present again,
GO to AN3. - AN3 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Visually inspect for:
- pushed out pins
- corrosion
- Connect all the PCM connectors and make sure they seat correctly.
- Carry out the PCM self-test and verify the concern is still present.
Is the concern still present?
Yes No INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) , Programming the VID Block for a Replacement PCM. The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.