Test Procedure
- RH1 PRELIMINARY DIAGNOSIS
Are DTCs P209F, P20B9, P20BA, P20BB, P20BC, P20BD, P20BE, P20BF, P20C0, P20C1, P20C2, P20C3, P20C4, P214F, P21DD, P221C or P221D present?
Yes No For F-150, GO to RH26.
For F-650/F-750 and F-Series Super Duty with DTCs P20BD, P20BF, P20BE, P20C0, P221C or P221D, GO to RH16.
For F-650/F-750 and F-Series Super Duty with DTCs P209F, P20B9, P20BA, P20BB, P20BC, P214F or P21DD, GO to RH8.
For Transit with DTCs P20BD, P20BE, P20BF, P20C0, P221C or P221D, GO to RH17.
For Transit with DTCs P209F, P20B9, P20BA, P20BB, P20BC, P214F or P21DD, GO to RH8.
For Transit with DTCs P20C1, P20C2, P20C3 or P20C4, GO to RH21.
For all others, GO to RH2.RETURN to SYMPTOM CHARTS for further direction. - RH2 CHECK THE REDUCTANT HEATER RELAY
- Carry out the reductant heater relay component test. Refer to the appropriate Wiring Diagrams, Component Testing article.
Is a concern present?
Yes No INSTALL a new Reductant Heater relay. Clear the PCM DTCs. REPEAT the self-test. GO to RH3. - RH3 CHECK THE REDUCTANT HEATER RELAY B+ CIRCUIT
- Reductant Heater Relay connector disconnected.
- Measure the voltage between:
(+) Reductant Heater Relay Connector, Harness Side (-) B+ Ground
Is the voltage greater than 10.5 V?
Yes No GO to RH4. REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test. - RH4 CHECK THE REDUCTANT HEATER RELAY GND CIRCUIT
Is the resistance less than 5 ohms?
Yes No GO to RH5. REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test. - RH5 CHECK THE REDUCTANT HEATER RELAY CIRCUITS FOR AN OPEN
- GPCM-C connector disconnected.
- Measure the resistance between:
(+) Reductant Heater Relay Connector, Harness Side (-) GPCM-C Connector, Harness Side RDHTRPWR RDHTRPWR - Pin 16 RDHTRCTRL RDHTRCTRL - Pin 2
Are the resistances less than 5 ohms?
Yes No GO to RH6. REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test. - RH6 CHECK THE REDUCTANT HEATER RELAY CIRCUITS FOR A SHORT TO GROUND
- Measure the resistance between:
(+) GPCM-C Connector, Harness Side (-) RDHTRPWR - Pin 16 Ground RDHTRCTRL - Pin 2 Ground
Are the resistances greater than 10K ohms?
Yes No GO to RH7. REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. - Measure the resistance between:
- RH7 CHECK THE REDUCTANT HEATER RELAY CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) GPCM-C Connector, Harness Side (-) RDHTRPWR - Pin 16 Ground RDHTRCTRL - Pin 2 Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. GO to RH38. - RH8 CHECK THE REDUCTANT DOSAGE CONTROL MODULE FOR VOLTAGE
- RH9 CHECK THE VOLTAGE TO THE REDUCTANT DOSAGE CONTROL MODULE RELAY
- Ignition OFF.
- Reductant Dosage Control Module Relay connector disconnected.
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) Reductant Dosage Control Module Relay Connector, Harness Side (-) B+ - Pin 1, 3 Ground Is the voltage greater than 10.5 V?
Yes No GO to RH10. REPAIR the open circuit.
Clear the RDCM and PCM DTCs. REPEAT the self-test.
- RH10 CHECK THE REDUCTANT DOSAGE CONTROL MODULE RELAY
- Carry out the reductant dosage control module relay component test. Refer to the appropriate Wiring Diagrams, Component Testing article.
Is a concern present?
Yes No INSTALL a new Reductant Dosage Control Module relay.
Clear the RDCM and PCM DTCs. REPEAT the self-test.GO to RH11. - RH11 CHECK THE REDUCTANT DOSAGE CONTROL MODULE CIRCUITS FOR AN OPEN
- Ignition OFF.
- Measure the resistance between:
(+) Reductant Dosage Control Module Relay Connector, Harness Side (-) Reductant Dosage Control Module Connector, Harness Side VPWR - Pin 5 VPWR - Pin 1, 3, 5, 51, 73 - Measure the resistance between:
(+) Reductant Dosage Control Module Connector, Harness Side (-) PWRGND - Pin 29, 7 Ground
Is the resistance less than 5 ohms?
Yes No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. REPAIR the open circuit.
Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH12 CHECK THE REDUCTANT TANK HEATER RESISTANCE
- Ignition OFF.
- For Transit,
- Reductant Heater and Sender Assembly connector disconnected.
- Measure the resistance between:
(+) Reductant Heater and Sender Assembly Connector, Component Side (-) Reductant Heater and Sender Assembly Connector, Component Side RDHTRC1 - Pin 1 GND - Pin 2 - For all others,
- Reductant Pump Assembly connector disconnected.
- Measure the resistance between:
(+) Reductant Pump Assembly Connector, Component Side (-) Reductant Pump Assembly Connector, Component Side RDHTRC1 GND
Is the resistance between 1 - 2.5 ohms?
Yes No GO to RH13. For Transit, INSTALL a new Reductant Heater and Sender assembly. REFER to the appropriate Engine Emission Control article.
Clear the PCM DTCs. REPEAT the self-test.
For all others, INSTALL a new Reductant Pump assembly. REFER to the appropriate Engine Emission Control article. Clear the RDCM and PCM DTCs. REPEAT the selftest. - RH13 CHECK THE REDUCTANT TANK HEATER CIRCUITS FOR AN OPEN
- For Transit,
- Reductant Dosage Control Module connector disconnected.
- Measure the resistance between:
(+) Reductant Heater and Sender Assembly Connector, Harness Side (-) Reductant Dosage Control Module Connector, Harness Side RDHTRC1 - Pin 1 RDHTRC1 - Pin 4 - Measure the resistance between:
(+) Reductant Heater and Sender Assembly Connector, Harness Side (-) GND - Pin 2 Ground - For all others,
- GPCM-C connector disconnected.
- Measure the resistance between:
(+) Reductant Pump Assembly Connector, Harness Side (-) GPCM-C Connector, Harness Side RDHTRC1 RDHTRC1 - Pin 15 - Measure the resistance between:
(+) Reductant Pump Assembly Connector, Harness Side (-) GND Ground
Are the resistances less than 5 ohms?
Yes No GO to RH14. REPAIR the open circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH14 CHECK THE RDHTRC1 CIRCUIT FOR A SHORT TO GROUND
- For Transit,
- Measure the resistance between:
(+) Reductant Heater and Sender Assembly Connector, Harness Side (-) RDHTRC1 - Pin 1 Ground - For all others,
- Measure the resistance between:
(+) Reductant Pump Assembly Connector, Harness Side (-) RDHTRC1 Ground
Is the resistance greater than 10K ohms?
Yes No GO to RH15. REPAIR the short circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH15 CHECK THE REDUCTANT TANK HEATER CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- For Transit,
- Measure the voltage between:
(+) Reductant Heater and Sender Assembly Connector, Harness Side (-) RDHTRC1 - Pin 1 Ground GND - Pin 2 Ground - For all others,
- Measure the voltage between:
(+) Reductant Pump Assembly Connector, Harness Side (-) RDHTRC1 Ground GND Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. For Transit, GO to RH25. - RH16 CHECK THE REDUCTANT PRESSURE LINE HEATER RESISTANCE
- Ignition OFF.
- Reductant Pressure Line Heater Assembly connector disconnected.
- Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Component Side (-) Reductant Pressure Line Heater Assembly Connector, Component Side RDHTRC2 GND
Is the resistance between 3 - 5 ohms?
Yes No For Transit, GO to RH17.
For all others, GO to RH18.INSTALL a new Reductant Pressure Line Heater assembly. REFER to the appropriate Engine Emission Control article. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH17 CHECK THE REDUCTANT PUMP ASSEMBLY HEATER RESISTANCE
- Reductant Pump Assembly connector disconnected.
- Measure the resistance between:
(+) Reductant Pump Assembly Connector, Component Side (-) Reductant Pump Assembly Connector, Component Side RDHTRC2 GND
Is the resistance between 2.5 - 6 ohms?
Yes No GO to RH18. INSTALL a new Reductant Pump assembly. REFER to the appropriate Engine Emission Control article. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH18 CHECK THE REDUCTANT PRESSURE LINE HEATER ASSEMBLY AND REDUCTANT PUMP ASSEMBLY CIRCUITS FOR AN OPEN
- For Transit,
- Reductant Dosage Control Module connector disconnected.
- Measure the resistance between:
(+) Reductant Pump Assembly Connector, Harness Side (-) Reductant Dosage Control Module Connector, Harness Side RDHTRC2 RDHTRC2 - Pin 2 - Measure the resistance between:
(+) Reductant Pump Assembly Connector, Harness Side (-) GND Ground - For all others,
- GPCM-C connector disconnected.
- Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) GPCM-C Connector, Harness Side RDHTRC2 RDHTRC2 - Pin 13 - Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) GND Ground
Are the resistances less than 5 ohms?
Yes No GO to RH19. REPAIR the open circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH19 CHECK THE RDHTRC2 CIRCUIT FOR A SHORT TO GROUND
- For Transit,
- Measure the resistance between:
(+) Reductant Pump Assembly Connector, Harness Side (-) RDHTRC2 Ground - For all others,
- Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) RDHTRC2 Ground
Is the resistance greater than 10K ohms?
Yes No GO to RH20. REPAIR the short circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH20 CHECK THE REDUCTANT PRESSURE LINE HEATER ASSEMBLY AND REDUCTANT PUMP ASSEMBLY CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- For Transit,
- Measure the voltage between:
(+) Reductant Pump Assembly Connector, Harness Side (-) RDHTRC2 Ground GND Ground - For all others,
- Measure the voltage between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) RDHTRC2 Ground GND Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. For Transit, GO to RH25.
For all others, GO to RH38. - RH21 CHECK THE REDUCTANT PRESSURE LINE HEATER RESISTANCE
- Ignition OFF.
- Reductant Pressure Line Heater Assembly connector disconnected.
- Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Component Side (-) Reductant Pressure Line Heater Assembly Connector, Component Side RDHTRC3 GND
Is the resistance between 3 - 5 ohms?
Yes No GO to RH22. INSTALL a new Reductant Pressure Line Heater assembly. REFER to the appropriate Engine Emission Control article. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH22 CHECK THE REDUCTANT PRESSURE LINE HEATER CIRCUITS FOR AN OPEN
- Reductant Dosage Control Module connector disconnected.
- Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) Reductant Dosage Control Module Connector, Harness Side RDHTRC3 RDHTRC3 - Pin 6 - Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) GND Ground
Are the resistances less than 5 ohms?
Yes No GO to RH23. REPAIR the open circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH23 CHECK THE RDHTRC3 CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) RDHTRC3 Ground
Is the resistance greater than 10K ohms?
Yes No GO to RH24. REPAIR the short circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. - Measure the resistance between:
- RH24 CHECK THE REDUCTANT PRESSURE LINE HEATER ASSEMBLY CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) RDHTRC3 Ground GND Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. GO to RH25. - RH25 CHECK FOR CORRECT REDUCTANT DOSAGE CONTROL MODULE OPERATION
- Reductant Dosage Control Module connector disconnected.
- Visually inspect for:
- pushed out pins
- corrosion
- Connect the reductant dosage control module connector and make sure it seats correctly.
- Carry out the DCU self-test.
- Verify the concern is still present.
Is the concern still present?
Yes No INSTALL a new Reductant Dosage Control module. REFER to the appropriate Electronic Engine Controls article. The system is operating correctly at this time.
The concern may have been caused by a loose or corroded connector. - RH26 F-150 DIAGNOSIS
Are DTCs P209F, P20B9, P20BA, P20BB, P20BC, P20BD, P20BE, P20BF, P20C0, P20C1, P20C2, P20C3, P20C4, P214F, P21DD, P221C or P221D present?
Yes No For DTCs P20BD, P20BF, P20BE, P20C0, P221C or P221D, GO to RH34.
For DTCs P209F, P20B9, P20BA, P20BB, P20BC, P214F or P21DD, GO to RH30.
For all others, GO to RH27.RETURN to SYMPTOM CHARTS for further direction. - RH27 CHECK THE BJB CIRCUITS FOR AN OPEN
- Ignition OFF.
- BJB-B connector disconnected.
- BJB-C connector disconnected.
- BJB-D connector disconnected.
- GPCM-C connector disconnected.
- Measure the resistance between:
(+) BJB-B Connector, Harness Side (-) GND - Pin 42 Ground - Measure the resistance between:
(+) BJB-C Connector, Harness Side (-) GPCM-C Connector, Harness Side RDHTRCTRL - Pin 28 RDHTRCTRL - Pin 2 - Measure the resistance between:
(+) BJB-D Connector, Harness Side (-) GPCM-C Connector, Harness Side RDHTRPWR - Pin 50 RDHTRPWR - Pin 16
Is the resistance less than 5 ohms?
Yes No GO to RH28. REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test. - RH28 CHECK THE REDUCTANT HEATER RELAY CIRCUITS FOR A SHORT TO GND
- Measure the resistance between:
(+) GPCM-C Connector, Harness Side (-) RDHTRPWR - Pin 16 Ground RDHTRCTRL - Pin 2 Ground
Are the resistances greater than 10K ohms?
Yes No GO to RH29. REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. - Measure the resistance between:
- RH29 CHECK THE REDUCTANT HEATER CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) GPCM-C Connector, Harness Side (-) RDHTRPWR - Pin 16 Ground RDHTRCTRL - Pin 2 Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. GO to RH38. - RH30 CHECK THE RDHTRC1 RESISTANCE
- Ignition OFF.
- Reductant Pump Assembly connector disconnected.
- Measure the resistance between:
(+) Reductant Pump Assembly Connector, Component Side (-) Reductant Pump Assembly Connector, Component Side RDHTRC1 GND
Is the resistance between 1 - 2.5 ohms?
Yes No GO to RH31. INSTALL a new Reductant Pump assembly. REFER to the appropriate Engine Emission Control article. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH31 CHECK THE RDHTRC1 CIRCUITS FOR AN OPEN
- Measure the resistance between:
(+) Reductant Pump Assembly Connector, Harness Side (-) GPCM-C Connector, Harness Side RDHTRC1 RDHTRC1 - Pin 15 - Measure the resistance between:
(+) Reductant Pump Assembly Connector, Harness Side (-) GND Ground
Are the resistances less than 5 ohms?
Yes No GO to RH32. REPAIR the open circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. - Measure the resistance between:
- RH32 CHECK THE REDUCTANT TANK HEATER CIRCUITS FOR A SHORT TO GROUND
- Measure the resistance between:
(+) Reductant Pump Assembly Connector, Harness Side (-) RDHTRC1 Ground
Is the resistance greater than 10K ohms?
Yes No GO to RH33. REPAIR the short circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. - Measure the resistance between:
- RH33 CHECK THE RDHTRC1 CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) Reductant Pump Assembly Connector, Harness Side (-) RDHTRC1 Ground GND Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. GO to RH38. - RH34 CHECK THE RDHTRC2 RESISTANCE
- Ignition OFF.
- Reductant Pressure Line Heater Assembly connector disconnected.
- Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Component Side (-) Reductant Pressure Line Heater Assembly Connector, Component Side RDHTRC2 GND
Is the resistance between 3 - 5 ohms?
Yes No GO to RH35. INSTALL a new Reductant Pressure Line Heater assembly. REFER to the appropriate Engine Emission Control article. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH35 CHECK THE RDHTRC2 AND REDUCTANT PUMP ASSEMBLY CIRCUITS FOR AN OPEN
- Ignition OFF.
- GPCM-C connector disconnected.
- Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) GPCM-C Connector, Harness Side RDHTRC2 RDHTRC2 - Pin 13 - Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) GND Ground
Are the resistances less than 5 ohms?
Yes No GO to RH36. REPAIR the open circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. - RH36 CHECK THE REDUCTANT PRESSURE LINE HEATER ASSEMBLY CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) RDHTRC2 Ground
Is the resistance greater than 10K ohms?
Yes No GO to RH37. REPAIR the short circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. - Measure the resistance between:
- RH37 CHECK THE RDHTRC2 AND REDUCTANT PUMP ASSEMBLY CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) Reductant Pressure Line Heater Assembly Connector, Harness Side (-) RDHTRC2 Ground GND Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the RDCM and PCM DTCs. REPEAT the self-test. GO to RH38. - RH38 CHECK FOR CORRECT GPCM OPERATION NOTE: Not all vehicles have all components listed.
- Disconnect all the GPCM connectors.
- Visually inspect for:
- pushed out pins
- corrosion
- Connect all the GPCM connectors and make sure they seat correctly.
- BJB-B connector connected.
- BJB-C connector connected.
- BJB-D connector connected.
- Reductant Heater Relay connector connected.
- Ignition ON, engine OFF.
- Clear the PCM DTCs.
- Carry out the KOER Glow Plug Monitor Self-Test using the scan tool.
- Carry out the PCM KOEO self-test.
- Verify the concern is still present.
Is the concern still present?
Yes No INSTALL a new GPCM. Refer to the appropriate Glow Plug System article.
Clear the PCM DTCs. REPEAT the self-test.The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.