Test Procedure

RJ1 PRELIMINARY DIAGNOSIS

Are DTCs P203A, P203B, P203C, P203D, P203E, P21AB or P21B0 present?

Yes	No
GO to RJ2 .	Unable to duplicate the condition. CHECK for a loose connection, and damaged or corroded terminals. WIGGLE the harness attempting to recreate the concern. REPAIR as necessary. RETURN to SYMPTOM CHARTS for further direction.

RJ2 CHECK THE REDUCTANT LEVEL CIRCUITS FOR AN OPEN

Ignition OFF.
Reductant Heater and Sender Assembly connector disconnected.
PCM-T connector disconnected.

Measure the resistance between:

(+) Reductant Heater and Sender Assembly Connector, Harness Side	(-) PCM-T Connector, Harness Side
RDL1 - Pin 6	RDL1 - Pin 15
RDL2 - Pin 7	RDL2 - Pin 18
RDL3 - Pin 8	RDL3 - Pin 19
RDLRTN - Pin 5	RDLRTN - Pin 32

Are the resistances less than 5 ohms?

Yes	No
GO to RJ3 .	For DTC P203E, REPAIR the open circuit. CARRY OUT the Selective Catalytic Reduction (SCR) System Procedure. REFER to DRIVE CYCLES . Clear the PCM DTCs. REPEAT the self-test. For all others, REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.

RJ3 CHECK THE REDUCTANT LEVEL CIRCUITS FOR A SHORT TO GROUND

Measure the resistance between:

(+) Reductant Heater and Sender Assembly Connector, Harness Side	(-)
RDL1 - Pin 6	Ground
RDL2 - Pin 7	Ground
RDL3 - Pin 8	Ground
RDLRTN - Pin 5	Ground

Are the resistances greater than 10K ohms?

Yes	No
GO to RJ4 .	REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test.

RJ4 CHECK THE REDUCTANT LEVEL CIRCUITS FOR A SHORT TO VOLTAGE

Ignition ON, engine OFF.

Measure the voltage between:

(+) Reductant Heater and Sender Assembly Connector, Harness Side	(-)
RDL1 - Pin 6	Ground
RDL2 - Pin 7	Ground
RDL3 - Pin 8	Ground
RDLRTN - Pin 5	Ground

Is any voltage present?

Yes	No
REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test.	GO to RJ5 .

RJ5 CHECK THE REDUCTANT LEVEL SENSOR FOR CORRECT OPERATION

NOTE: Make sure all pins are jumpered at the same time.

Ignition OFF.
PCM-T connector connected.

Connect a 5 amp fused jumper wire between the following:

Point A Reductant Heater and Sender Assembly Connector, Harness Side	Point B Reductant Heater and Sender Assembly Connector, Harness Side
RDL1 - Pin 6	RDLRTN - Pin 5
RDL2 - Pin 7	RDLRTN - Pin 5
RDL3 - Pin 8	RDLRTN - Pin 5
RDT - Pin 3	RDLRTN - Pin 5

Ignition ON, engine OFF.
Access the PCM and monitor the REDUCT_TNK_LV (PER) PID.

Is the PID value 100%?

Yes	No
For DTC P203E, INSTALL a new Reductant Heater and Sender assembly. REFER to the service information , Engine Emission Control. CARRY OUT the Selective Catalytic Reduction (SCR) System Procedure. REFER to DRIVE CYCLES . Clear the PCM DTCs. REPEAT the self-test. For all others, INSTALL a new Reductant Heater and Sender assembly. REFER to the service information , Engine Emission Control. Clear the PCM DTCs. REPEAT the self-test.	GO to RJ6 .

Yes

For DTC P203E, INSTALL a new Reductant Heater and Sender assembly.
REFER to the service information , Engine Emission Control.
CARRY OUT the Selective Catalytic Reduction (SCR) System Procedure. REFER to DRIVE CYCLES .
Clear the PCM DTCs. REPEAT the self-test.
For all others, INSTALL a new Reductant Heater and Sender assembly.
REFER to the service information , Engine Emission Control.
Clear the PCM DTCs. REPEAT the self-test.

GO to RJ6 .

RJ6 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.
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) .	The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.