Diagnostic Test
WARNING: This page is about a different car, the 2013 RAM 3500 HD and 2013 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
- ACTIVE DTC
- CHECK THE NOx 1/2 SENSOR INTERNAL HEATER
- Start the engine and allow it to idle for at least two minutes.
- With the scan tool, View DTCs.
Is the DTC active?
Yes
- The NOx Sensor 1/2 internal heater has malfunctioned. Replace the NOx Sensor 1/2 in accordance with the service information. Refer to SENSOR, NOX, REMOVAL .
No
- Go To 3
- CHECK THE NOx SENSOR 1/2 POWER AND GROUND CIRCUITS
- Turn the ignition on, engine not running.
- Disconnect the NOx Sensor Module 1/2 harness connector.
- Measure the voltage across the (F204) Fused Ignition Switch Output circuit and the (Z915) Ground circuit at the NOx Sensor Module 1/2 harness connector.NOTE:
Measure the voltage at key on, engine cranking, and at idle.
Does the voltage read within 1.0 Volt of battery voltage?
Yes
- Replace the NOx Sensor 1/2 in accordance with the service information. Refer to SENSOR, NOX, REMOVAL .
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Go To 4
- CHECK FOR VOLTAGE AT THE (F204) FUSED IGNITION SWITCH OUTPUT CIRCUIT
- Measure voltage between ground and the (F204) Fused Ignition Switch Output circuit of the NOx Sensor Module 1/2 harness connector.
Does the voltage read within 1.0 Volt of battery voltage?
Yes
- Repair the (Z915) Ground circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
No
- Repair the (F204) Fused Ignition Switch Output circuit for an open or high resistance. If the fuse is found to be open, check the circuit for a short to the (Z915) Ground circuit or a short to chassis ground.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
- Measure voltage between ground and the (F204) Fused Ignition Switch Output circuit of the NOx Sensor Module 1/2 harness connector.