Mil On/DTC P0141 Stored - Install New Rear O2 Sensor (96-T-21A)

MIL ON/DTC P0141 STORED - INSTALL NEW REAR O2 SENSOR

TECHNICAL SERVICE BULLETIN

MIL ON AND/OR DTC P0141 STORED IN PCM MEMORY (INSTALL NEW REAR HEATED OXYGEN SENSOR AND PCM CALIBRATION)

APPLICATION

Model: 1996 Saturns

Group/Seq. No.: Engine - 05

Corp. No. 686505R

Bulletin No.: 96-T-21A

Date: August, 1996

CONDITION

The malfunction indicator lamp (MIL) (SERVICE ENGINE SOON telltale lamp) may be On with diagnostic trouble code (DTC) P0141 stored in powertrain control module (PCM) malfunction history.

CAUSE

The rear heated oxygen sensor internal element may be fractured or shorted, causing an inoperative heater function.

CORRECTION

Refer to the following procedures to repair this condition. After condition is repaired, download a new service calibration on vehicles built before and including VIN TZ201459 (automatic transaxle) or VIN TZ201811 (manual transaxle). This new calibration revises parameters that result in false fails for inactivity of the rear heated oxygen sensor, preventing DTC P0140.

PROCEDURES

1. Connect Scan tool to DLC and access diagnostic trouble codes (DTCs).
   1. If DTC P0141 is only DTC present, proceed to step 2 and replace rear heated oxygen sensor.
   2. If DTCs P0440, P0443 or P1406 are present along with DTC P0141, check the EGR fuse located in the underhood junction block (UHJB). If the fuse has opened, disconnect the rear heated oxygen sensor and verify that the short is no longer present. If short is no longer present, replace the EGR fuse and proceed to step 2 and replace the rear heated oxygen sensor.
   3. If the short remains, refer to the appropriate diagnostics in the "1996 Powertrain Controls Service Manual" to repair the condition. After condition has been repaired, proceed to step 14 of this bulletin, and if applicable, download the new service calibration.
2. Disconnect negative battery cable.
   CAUTION: Make sure vehicle is properly supported and squarely positioned. To help avoid personal injury when a vehicle is on a hoist, provide additional support from the opposite end from which components are being removed. Make sure hoist DOES NOT contact fuel or brake lines.
3. Raise vehicle squarely on a hoist.
4. Remove rear heated oxygen sensor wiring harness from the cradle by pushing up on retaining clip tab. See Fig 1 .
5. Remove Connector Position Assurance (CPA) device and disconnect rear heated oxygen sensor wiring harness from engine wiring harness. See Fig 2 .
6. Remove the rear heated oxygen sensor wiring harness from the three-way catalytic converter heat shield trough by gently pushing the wiring harness from its retaining clips. See Fig 3 .
7. Remove rear heated oxygen sensor using Saturn tool SA9603E. If necessary, use a liquid penetrate before removing rear heated oxygen sensor.
   NOTE: The rear heated oxygen sensor uses a permanently attached pigtail and connector. This pigtail should NOT be removed from the oxygen sensor. Damage to, or removal of the pigtail or connector could affect proper operation of the rear heated oxygen sensor.
   NOTE: Service replacement oxygen sensors have a sufficient amount of anti-seize compound; therefore, additional anti-seize compound is NOT recommended.
8. Install rear heated oxygen sensor using Saturn tool SA9603E. See Fig 4 . Torque: 4 N.m (33 ft-lb).
   NOTE: Make sure to center the white marker tape on the rear heated oxygen sensor pigtail with the edge of the trough. The white marker tape must be centered with the edge of the trough to ensure there will be no stress on the sensor connection.
9. Connect rear heated oxygen sensor wiring harness connector into engine wiring harness connector. See Fig 2 .
10. Install the Connector Position Assurance (CPA) device into the electrical connector.
11. Install rear heated oxygen sensor wiring harness retaining clips into cradle.
12. Lower vehicle.
13. Connect negative battery cable.
14. On vehicles built before and including VIN TZ201454 (automatic transaxle) or VIN TZ221884 (manual transaxle) select the following through the Scan tool menus:
    1. 1996 Vehicle.
    2. PCM/EC.
    3. Scanner.
    4. Vehicle ID Table.
    5. Compare END MODEL # to the following "1996 Purge Diagnostic Enhancement Calibrations" chart:
       • If End Model # displayed on Scan tool is listed in the "PRIOR END MODEL #" column, download a new service calibration using the EEPROM programming feature of the Service Stall System (SSS). (Refer to "PCM Flash Programming" under "General Description" in the "PCM Serial Data" section of the "1996 Revised Powertrain Controls Service Manual," or the "Service Stall Users Guide" for proper programming procedures.)
       • If the End Model # displayed on Scan tool is listed in the "END MODEL #" column, the new service calibration has already been downloaded and there is no need to download a new service calibration.

End Model #	Calibration Description	Prior End Model #
---	Base Manual Calibrations	---
21008149	B/M Federal - Purge Diagnostic Enhancement	21008053
21008150	B/M California - Purge Diagnostic Enhancement	21008054
21008154	B/M Canada - Purge Diagnostic Enhancement	21008066
21008154	B/M Taiwan - Purge Diagnostic Enhancement	21008066
---	Base Automatic Calibrations	---
21008145	B/A Federal - Purge Diagnostic Enhancement	21008071 21008049
21008146	B/A California - Purge Diagnostic Enhancement	21008072 21008050
21008152	B/A Canada - Purge Diagnostic Enhancement	21008074 21008064
21008152	B/A Taiwan - Purge Diagnostic Enhancement	21008074 21008064
---	Performcance Manual Calibrations	---
21008147	P/M Federal - Purge Diagnostic Enhancement	21008051
21008148	P/M California - Purge Diagnostic Enhancement	21008052
21008153	P/M Taiwan - Purge Diagnostic Enhancement	21008065
21008153	P/M Canada - Purge Diagnostic Enhancement	21008065
---	Performcance Automatic Calibratons	---
21008144	P/A California & Federal - Purge Diagnostic Enhancement	21008048
21008151	P/A Canada - Purge Diagnostic Enhancement	21008063
21008151	P/A Taiwan - Purge Diagnostic Enhancement	21008063

PARTS INFORMATION

Part Number	Description
25167115	Sensor Asm-Heated Oxygen

WARRANTY INFORMATION

To receive credit for this repair during the warranty coverage period, submit a claim through the Saturn Dealer System for J6380 (replace rear heated oxygen sensor), or if another procedure is performed, refer to the appropriate Electronic Labor Time Guide for the correct Labor Operation Code and Time.