DTC P0141: HEATED OXYGEN SENSOR HEATER CIRCUIT
CAUTION: If ECM replacement is instructed in following testing, always
ensure ECM connectors and ground circuit are okay. If either
are suspect, repair and repeat testing to confirm ECM
malfunction.
NOTE: Bank No. 1 refers to bank that includes cylinder No. 1. Bank
No. 2 refers to bank without cylinder No. 1. Oxygen sensor No.
1 refers to sensor closest to engine block. Oxygen sensor No.
2 refers to sensor furthest away from engine block.
Condition
DTC P0141 is for bank No. 1, sensor No. 2. DTC is set when either of the
following conditions is present:
- Sensor heater current draw exceeds 2 amps.
- Sensor heater current draw is .25 amp or less when heater operates.
Possible causes are:
- Heated oxygen sensor open or short circuit. l
- Heated oxygen sensor heater.
- ECM.
Diagnosis & Repair
1.Access ECM behind glove box. Turn ignition on. On models with Calif.
emissions and except Calif. emissions with engine immobilizer system
and/or traction control, backprobe ECM connector and measure voltage
between ground and terminal No. 9 (Pink/Black wire) at ECM E8
connector. See Fig. 2. On except Calif. emission models without
engine immobilizer system and/or traction control, backprobe ECM
connector and measure voltage between ground and terminal No. 17
(Pink/Black wire) at ECM E7 connector. See Fig. 3.
NOTE: For information on engine immobilizer system, see
COMPUTERIZED ENGINE CONTROLS in E - THEORY/OPERATION
article.
2.On all models, voltage should be 9-14 volts. If voltage is as
specified, replace ECM. If voltage is not as specified, turn ignition
off. Disconnect bank No. 1, sensor No. 2 connector. Connector is
located on underneath carpet on driver's side, near center console.
If may be necessary to remove driver's seat to access connector.
Using ohmmeter, measure resistance between terminals No. 1
(Pink/Black wire) and No. 2 (Black/Yellow wire) at oxygen sensor
connector.
3.If resistance is 11-16 ohms at 68°F (20°C), check wiring harness
between ECM and oxygen sensor. See appropriate wiring diagram in L -
WIRING DIAGRAMS article. Repair wiring as necessary. If resistance is
not 11-16 ohms at 68°F (20°C), replace oxygen sensor.