Component Testing
WARNING: This page is about a different car, the 2017 Cadillac ATS. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect and remove the KR33 Auxiliary Heater Coolant Pump Relay.
- Test for 70-110 Ω between terminals 85 and 86.
- If less than 70 Ω or greater than 110 Ω
Replace the KR33 Auxiliary Heater Coolant Pump Relay
- If between 70-110 Ω
- If less than 70 Ω or greater than 110 Ω
- Test for infinite resistance between the terminals listed below:
- 30 and 86
- 30 and 87
- 30 and 85
- 85 and 87
- If less than infinite resistance
Replace the KR33 Auxiliary Heater Coolant Pump Relay
- If infinite resistance
- Install a 3 A fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground.
- Test for less than 2 Ω between terminals 30 and 87
- If 2 Ω or greater
Replace the KR33 Auxiliary Heater Coolant Pump Relay
- If less than 2 Ω
- If 2 Ω or greater
- All OK