Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.

NOTE: The reductant temperature must be greater than -7°C (+19°F) before proceeding.

Test the reductant for contamination. Refer to Contaminants-in-Diesel Exhaust Fluid Diagnosis .
- If contaminated
  Repair as necessary
- If not contaminated
Ignition On.
Command the Reductant System Leak Test On with a scan tool. Allow the pressure to build for 2 minutes. Verify there are no leaks in the reductant lines.
- If a condition is found
  Repair as necessary
- If no condition is found
Remove the Q61 Emission Reduction Fluid Injector from the exhaust pipe leaving the reductant line and electrical connector connected. Place the injector into a suitable container.
Command the Reductant System Leak Test On with a scan tool. Allow the pressure to build. The injector should not leak.
- If a condition is found
  Replace the Q61 Emission Reduction Fluid Injector
- If no condition is found
Command the Reductant System Leak Test On with a scan tool. Allow the pressure to build. Observe the scan tool Reductant Pressure sensor parameter. The reading should be greater than 400 kPa (58 psi).
- If unable to build pressure
  Replace the A38 Emission Reduction Fluid Supply Pump Module
- If able to build pressure
Perform the Reductant Injection Quantity Test . The test should pass.
Verify the following conditions do not exist with the reductant system:
- Missing, restricted or leaking reductant components
- Restricted or plugged reductant lines
- Stuck closed, restricted or plugged Q62 Reductant Purge Valve
- High resistance in the G33 Reductant Pump Motor or Q62 Reductant Purge Valve circuits
- Inspect the harness connectors and the ground circuits of the reductant tank for poor connections
- If a condition is found
  Repair as necessary
- If no condition is found
Replace the A38 Emission Reduction Fluid Supply Pump Module.