PINPOINT TEST G531332p7 : RIGHT-HAND H02S HEATER CONTROL CIRCUIT HIGH/LOW CURRENT

Pinpoint Tests

PINPOINT TEST G531332p7 : RIGHT-HAND H02S HEATER CONTROL CIRCUIT HIGH/LOW CURRENT

G531332t23 : CHECK H02S HEATER POWER SUPPLY CIRCUIT
1. Key off.
2. Disconnect the H02S electrical connector, PI10.
3. Key on, engine off.
4. Make sure the O2S heater relay is engaged.
5. Measure the voltage between:

HO2S connector PI10, Battery
harness side
Pin 01 Negative terminal

- Is the voltage greater than 10 volts?

-> YES
GO to Pinpoint Test G531332t24.

-> NO
REPAIR the power supply circuit to the H02S heater. This circuit includes the HO2S heater relay, fuse 34 of the front power distribution box, and the high power protection module. CLEAR the DTC. TEST the system for normal operation.

G531332t24 : 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 PI10, ECM connector PI300,
harness side harness side
Pin 02 Pin 76

- 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 G531332t25.

G531332t25 : CHECK H02S HEATER CONTROL CIRCUIT FROM ECM FOR SHORT CIRCUIT TO POWER
1. Key on, engine off.
2. Measure the voltage between:

HO2S connector PI10, 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 G531332t26.

G531332t26 : CHECK H02S HEATER CONTROL CIRCUIT FROM ECM FOR SHORT CIRCUIT TO GROUND
1. Key off.
2. Measure the resistance between:

HO2S connector PI10, 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.