Circuit/System Testing
WARNING: This page is about a different car, the 2010 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Use the connector test adapter kit J 35616-A for any test that requires probing the following items:
Using this kit will prevent damage caused by the improper probing of connector terminals.
- The control module harness connectors
- The electrical center fuse/relay cavities
- The component terminals
- The component harness connector
Using this kit will prevent damage caused by the improper probing of connector terminals.
- Ignition OFF, disconnect harness connector X2 at the K20 ECM.
- Connect a test lamp between terminal X2-45 and ground.
- A DMM connected between the test lamp probe and ground will measure 5-6 V if the test lamp illuminates with low intensity. The voltage will measure near B+ if the test lamp illuminates with bright intensity.
- The values listed above are based on the use of the J-35616-210 test lamp, or a comparable test lamp that has approximately 30 Ω of internal resistance.
- Ignition ON, connect a fused jumper wire between the powertrain relay control circuit terminal X2-58 and ground. The test lamp should illuminate with low intensity.
- If the test lamp does not illuminate, test the auxiliary coolant pump relay control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the X50A underhood fuse block (UBEC).
- If the test lamp illuminates with bright intensity, test the auxiliary coolant pump relay control circuit for a short to voltage. If the circuit tests normal, test or replace the X50A UBEC.
- If all circuits/connections test normal, replace the K20 ECM.
NOTE:
Refer to Diagnostic Aids before performing the Circuit/System Testing.
NOTE: