PINPOINT TEST G531332p11 : LEFT-HAND H02S HEATER CONTROL CIRCUIT HIGH/LOW CURRENT

Pinpoint Tests

PINPOINT TEST G531332p11 : LEFT-HAND H02S HEATER CONTROL CIRCUIT HIGH/LOW CURRENT

G531332t39 : CHECK H02S HEATER POWER SUPPLY CIRCUIT
1. Key off.
2. Disconnect the H02S electrical connector, PI12.
3. Key on, engine off.
4. Measure the voltage between:

HO2S connector PI12, Battery
harness side
Pin 01 Negative terminal

- Is the voltage greater than 10 volts?

-> YES
GO to Pinpoint Test G531332t40.

-> 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.

G531332t40 : CHECK H02S HEATER CONTROL CIRCUIT FROM ECM FOR HIGH RESISTANCE
1. Key off.
2. Disconnect the ECM electrical connector, PI300.
3. Measure the resistance between:

HO2S connector PI12, ECM connector PI300,
harness side harness side
Pin 02 Pin 77

- Is the resistance greater than 5 ohms?

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

-> NO
GO to Pinpoint Test G531332t41.

G531332t41 : CHECK H02S HEATER CONTROL CIRCUIT FROM ECM FOR SHORT CIRCUIT TO POWER
1. Key on, engine off.
2. Measure the voltage between:

HO2S connector PI12, Battery
harness side
Pin 02 Negative terminal

- Is the voltage greater than 3 volts?

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

-> NO
GO to Pinpoint Test G531332t42.

G531332t42 : CHECK H02S HEATER CONTROL CIRCUIT FROM ECM FOR SHORT CIRCUIT TO GROUND
1. Key off.
2. Measure the resistance between:

HO2S connector PI12, Battery
harness side
Pin 02 Negative terminal

- Is the resistance less than 10,000 ohms?

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

-> NO
INSTALL a new H02S. 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.