PINPOINT TEST G258127p11

Pinpoint Tests

PINPOINT TEST G258127p11 : DTC P0051, P0052; LEFT-HAND H02S HEATER CONTROL CIRCUIT HIGH/LOW CURRENT

G258127t39 : CHECK H02S HEATER POWER SUPPLY CIRCUIT
1. Disconnect the H02S electrical connector, PI12.
2. Turn the ignition switch to the ON position.
3. Measure the voltage between PI12, pin 01 (WR) and GROUND.

- Is the voltage greater than 10 volts?

->YES
GO to Pinpoint Test G258127t40.

->NO
REPAIR the power supply circuit to the H02S heater. This circuit includes the heater relay, fuse 33 of the front power distribution box, and the high power protection module. CLEAR the DTC. TEST the system for normal operation.

G258127t40 : CHECK H02S HEATER CONTROL CIRCUIT FROM ECM FOR HIGH RESISTANCE
1. Disconnect the battery negative terminal.
2. Disconnect the ECM electrical connector, PI01.
3. Measure the resistance between PI12, pin 02 (RW) and PI01, pin 55 (RW).
4. Measure the resistance between PI12, pin 02 (RW) and PI01, pin 56 (RW).

- Is either 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 G258127t41.

G258127t41 : CHECK H02S HEATER CONTROL CIRCUIT FROM ECM FOR SHORT TO HIGH VOLTAGE
1. Reconnect the battery negative terminal.
2. Turn the ignition switch to the ON position.
3. Measure the voltage between PI12, pin 02 (RW) and GROUND.

- Is the voltage greater than 3 volts?

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

->NO
GO to Pinpoint Test G258127t42.

G258127t42 : CHECK H02S HEATER CONTROL CIRCUIT FROM ECM FOR SHORT TO GROUND
1. Turn the ignition switch to the OFF position.
2. Measure the resistance between PI12, pin 02 (RW) and GROUND.

- Is the resistance less than 10,000 Ohms?

->YES
REPAIR the short circuit to GROUND. 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, contact dealer technical support for advice on possible ECM failure.