PINPOINT TEST G531332p12 : LEFT-HAND CATALYST MONITOR SENSOR HEATER CONTROL CIRCUIT LOW/HIGH RESISTANCE

Pinpoint Tests

PINPOINT TEST G531332p12 : LEFT-HAND CATALYST MONITOR SENSOR HEATER CONTROL CIRCUIT LOW/HIGH RESISTANCE

G531332t43 : CHECK THE POWER SUPPLY TO THE CATALYST MONITOR SENSOR HEATER
1. Disconnect the catalyst monitor sensor electrical connector, PI13.
2. Key on, engine off.
3. Make sure the catalyst monitor sensor heater relay is engaged. 4. Measure the voltage between:

Catalyst monitor sensor Battery
connector PI13, harness side
Pin 01 Negative terminal

- Is the voltage greater than 10 volts?

-> YES
GO to Pinpoint Test G531332t44.

-> No
REPAIR the power supply circuit to the H02S heater. This circuit includes the heater relay and fuse 34 of the front power distribution box. CLEAR the DTC. TEST the system for normal operation.

G531332t44 : CHECK THE CATALYST MONITOR SENSOR HEATER CONTROL CIRCUIT FOR HIGH RESISTANCE
1. Key off.
2. Disconnect the ECM electrical connector, PI300.
3. Measure the resistance between:

Catalyst monitor sensor ECM connector PI300,
connector PI13, harness side harness side
Pin 01 Pin 89

- Is the resistance greater than 5 ohms?

-> YES
REPAIR the high resistance circuit. CLEAR the DTC. TEST the system for normal operation.

-> NO
INSTALL a new catalyst monitor sensor. CLEAR the DTC. TEST the system for normal operation. If the DTC is repeated, refer to the warranty policy and procedures manual if an ECM is suspect.