PINPOINT TEST G258127p12

Pinpoint Tests

PINPOINT TEST G258127p12 : DTC P0057, P0058; LEFT-HAND CATALYST MONITOR SENSOR HEATER CONTROL CIRCUIT LOW/HIGH RESISTANCE

G258127t43 : CHECK THE POWER SUPPLY TO THE CATALYST MONITOR SENSOR HEATER
1. Disconnect the catalyst monitor sensor electrical connector, PI13.
2. Turn the ignition switch to the ON position.
3. Make sure the O2S heater relay is engaged.
4. Measure the voltage between PI13, pin 01 (WR) and GROUND.

- Is the voltage greater than 10 volts?

->YES
GO to Pinpoint Test G258127t44.

->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.

G258127t44 : CHECK THE CATALYST MONITOR SENSOR HEATER CONTROL CIRCUIT FOR HIGH RESISTANCE
1. Disconnect the battery negative terminal.
2. Disconnect the ECM electrical connector, PI01.
3. Measure the resistance between PI13, pin 02 (RW) and PI01, pin 93 (RW).

- 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, contact dealer technical support for advice on possible ECM failure.