P0136

F1 : CHECK THE VOLTAGE AND SIGNAL GROUND SUPPLY TO THE CATALYST MONITOR SENSOR
1. Switch the ignition switch to the OFF position.
2. Raise and support the vehicle. Service and Repair
3. Disconnect the right hand catalyst monitor sensor electrical connector GB3.
4. Switch the ignition switch to the RUN position.
5. Measure the voltage between the right hand catalyst monitor sensor electrical connector GB3 pin 1, and pin 3.

Is the voltage greater than 10.5 volts?

Yes
Go to F3

No
Go to F2


F2: CHECK THE CATALYST MONITOR SENSOR VOLTAGE SUPPLY CIRCUIT
1. Measure the voltage between the right hand catalyst monitor sensor electrical connector GB3 pin 1, (GR) and ground.

Is the voltage greater than 10.5 volts?

Yes
REPAIR the circuit between the right hand catalyst monitor sensor electrical connector GB3 pin 2, (BO) and the powertrain electrical connector GB1 pin 15, (BO). CLEAR DTC. TEST the system for normal operation.

No
REPAIR the circuit between the right hand catalyst monitor sensor electrical connector GB3 pin 1, (GR) and the spliced joint GBS1. CLEAR DTC. TEST the system for normal operation.


F3: CHECK THE CATALYST MONITOR SENSOR HEATER CONTINUITY
1. Switch the ignition switch to the OFF position.
2. Measure the resistance between the right hand catalyst monitor sensor electrical connector GB3 pin 1, and pin 2.

Is the resistance between 3 and 10 ohms?

Yes
Go to F4

No
INSTALL a new right hand catalyst monitor sensor. CLEAR DTC. TEST the system for normal operation.


F4: CHECK THE CATALYST MONITOR SENSOR FOR FAILURE
1. Connect the right hand catalyst monitor sensor electrical connector GB3.
2. RUN the engine until the catalyst monitor sensor has warmed up and maintain a speed of approximately 2500 rpm.
3. Disconnect the right hand catalyst monitor sensor electrical connector GB3.
4. Measure the voltage between the right hand catalyst monitor sensor electrical connector GB3 pin 3, and pin 4.

Is the voltage between 600mV and 1.0 Volt?

Yes
Go to F5

No
INSTALL a new right hand catalyst monitor sensor. CLEAR DTC. TEST the system for normal operation.


F5: CHECK THE CATALYST MONITOR SENSOR FOR FAILURE
1. Connect the right hand catalyst monitor sensor electrical connector GB3.
2. REDUCE the engine speed to idle.
3. Disconnect the right hand catalyst monitor sensor electrical connector GB3.
4. Measure the voltage between the right hand catalyst monitor sensor electrical connector GB3 pin 3, and pin 4.

Has the voltage dropped to less than 400mV?

Yes
Go to F6

No
INSTALL a new right hand catalyst monitor sensor. CLEAR DTC. TEST the system for normal operation.


F6: CHECK THE CATALYST MONITOR SENSOR FOR FAILURE
1. Connect the catalyst monitor sensor electrical connector GB3.
2. INCREASE the engine speed to approximately 2500 rpm.
3. Disconnect the catalyst monitor sensor electrical connector GB3.

Has the voltage increased to between 600 mV to 1.0 Volt?

Yes
Go to F7

No
INSTALL a new catalyst monitor sensor. CLEAR DTC. TEST the system for normal operation.


F7: CHECK THE CATALYST MONITOR SENSOR FOR SHORT TO GROUND
1. Switch the ignition switch to the OFF position.
2. Disconnect the oxygen sensor electrical connector GB3.
3. Measure the resistance between the catalyst monitor sensor electrical connector GB3 pin 1, (GR) and the monitor sensor body, and between the catalyst monitor sensor electrical connector GB3 pin 3, (NU) and the monitor sensor body.

Is the resistance greater than 10 M ohms?

Yes
Go to F8

No
INSTALL a new catalyst monitor sensor. CLEAR DTC. TEST the system for normal operation.


F8: CHECK THE CATALYST MONITOR SENSOR SIGNAL GROUND CIRCUIT FOR OPEN
1. Measure the resistance between the catalyst monitor sensor electrical connector GB3 pin 3, (NU) and ground.

Is the resistance greater than 10,000 ohms?

Yes
REPAIR the circuit between the catalyst monitor sensor electrical connector GB3 pin 3, (NU) and the spliced joint GBS3. CLEAR DTC. TEST the system for normal operation.

No
Go to F9


F9: CHECK THE CATALYST MONITOR SENSOR INPUT CIRCUIT FOR OPEN
1. Remove the powertrain control module (PCM).
2. Measure the resistance between the catalyst monitor sensor electrical connector GB3 pin 4, (WU) and the powertrain control module electrical connector GB1 pin 28, (WU).

Is the resistance greater than 10,000 ohms?

Yes
REPAIR the circuit between the catalyst monitor sensor electrical connector GB3 pin 4, (WU) and the powertrain control module electrical connector GB1 pin 28, (WU). INSTALL the powertrain control module (PCM). CLEAR DTC. TEST the system for normal operation.

No
Go to F10


F10: CHECK THE CATALYST MONITOR SENSOR CIRCUIT FOR SHORT TO GROUND
1. Measure the resistance between the catalyst monitor sensor electrical connector GB3 pin 4, (WU) and ground.

Is the resistance less than 10,000 ohms?

Yes
REPAIR the input circuit between the catalyst monitor sensor electrical connector GB3 pin 4, (WU) and the powertrain control module electrical connector GB1 pin 28, (WU). INSTALL the powertrain control module (PCM). CLEAR DTC. TEST the system for normal operation.

No
Go to F11


F11: CHECK THE CATALYST MONITOR SENSOR HEATER CIRCUIT FOR OPEN
1. Measure the resistance between the catalyst monitor sensor electrical connector GB3 pin 2, (BO) and the powertrain control module electrical connector GB1 pin 15, (BO).

Is the resistance greater than 10,000 ohms?

Yes
REPAIR the output circuit between the catalyst monitor sensor electrical connector GB3 pin 2, (BO) and the powertrain control module electrical connector GB1 pin 15, (BO). INSTALL the powertrain control module (PCM). CLEAR DTC. TEST the system for normal operation.

No
Go to F12


F12: CHECK THE OXYGEN SENSOR HEATER CIRCUIT FOR SHORT TO GROUND
1. Measure the resistance between the catalyst monitor sensor electrical connector GB3 pin 2, (BO) and ground.

Is the resistance less than 10,000 ohms?

Yes
REPAIR the output circuit between the catalyst monitor sensor electrical connector GB3 pin 2, (BO) and the powertrain control module electrical connector GB1 pin 15, (BO). INSTALL the powertrain control module (PCM). CLEAR DTC. TEST the system for normal operation.

No
Go to F13


F13: CHECK THE CATALYST MONITOR SENSOR SIGNAL GROUND CIRCUIT FOR SHORT TO GROUND
1. Disconnect both catalyst monitor sensor electrical connectors GB3, GB4.
2. Measure the resistance between the catalyst monitor sensor electrical connector GB3 pin 3, (NU) and ground.

Is the resistance less than 10,000 ohms?

Yes
REPAIR the signal ground circuit between the catalyst monitor sensor electrical connector GB3 pin 3, (NU) and the spliced joint GBS3. INSTALL the powertrain control module (PCM). CLEAR DTC. TEST the system for normal operation.

No
INSTALL a new powertrain control module (PCM). CLEAR DTC. TEST the system for normal operation.