PCM - Calibration Enchancement
File In Section: 6E - Engine Fuel & EmissionBulletin No.: 67-65-25B
Date: March, 1997
INFORMATION
Subject:
PCM Calibration Enhancement
Models:
1996 Cadillac DeVille, DeVille Concours, Eldorado, Eldorado ETC, Seville SLS, Seville STS
1996 Oldsmobile Aurora
with 4.0L, 4.6L Engines (VINs C, V, 9 - RPOs L47, LD8, L37)
This bulletin is being revised for additional DTC codes. Please discard
Corporate Bulletin Number 67-65-25A (Section 6E - Engine Fuel and Emission).
A PCM calibration enhancement has been released for the 4.0L and 4.6L engines identified above. This PCM calibration enhancement is located on Techline CD ROM disc # 4 1997. This PCM calibration can be used to service 1996 model year 4.0L and 4.6L engines with the following DTC codes after following the complete instructions below for each DTC code listed.
For any DTC codes without asterisk, proceed to the Parts Information section of this bulletin. If any of the DTC codes with asterisk above are present, carefully follow the steps listed.
Important:
All DTC codes, technician observations and customer comments must be recorded on the repair order in accordance with Article 1.6.2 G of the General Motors Service Policies and Procedure Manual.
Verify if the vehicle has been previously updated with an enhanced calibration from Techline CD ROM disc # 4 1997. If the vehicle was updated with an enhanced calibration from Techline CD ROM disc # 4 1997, then consult the diagnostic procedures for the specific DTC codes listed in Section 6E of the applicable Service Manual. If the vehicle was not updated with an enhanced calibration from Techline CD ROM disc # 4 1997, then proceed to the specific DTC code listed and follow the instructions for that code completely.
For 02 Response and Ratio DTC Codes P0133, P0153, P1134, and P1154
Verify 02 heater operation using the appropriate Service Manual Section 6E diagnostic charts. Follow the DTC diagnostic chart to the point where it recommends replacing the oxygen sensor. Update PCM with applicable calibration listed in the Parts Information section of this bulletin. Do NOT replace oxygen sensor. Verify the repair using the Tech II device.
For 02 response ratio pre-converter 02 DTC code P1140
Verify 02 heater operation using the service manual section DTC diagnostic chart. Follow the diagnostic chart to the point where it recommends replacing the oxygen sensor. Update PCM with applicable calibration listed in the Parts Information section of this bulletin. Do NOT replace oxygen sensor. Verify the repair using the Tech II device.
For EGR System Malfunction DTC code: P0401
This DTC code is more likely to set by frequent vehicle hot starts in high ambient temperatures. Verify that there are no induction system leaks. If no induction system leaks are found, proceed to the service manual DTC diagnostic chart. If at step 7 of the DTC diagnostic chart, the answer is "yes", then update the PCM with the applicable calibration listed in the Parts Information section of this bulletin. Verify the repair using the Tech II device.
Parts Information
After following the specific instructions outlined above, and if performing all necessary procedures in the Service Manual indicate that a calibration enhancement is required, then update the vehicle with the applicable enhanced calibration listed.
Warranty Information
For vehicles repaired under warranty, use:
For all 1996 Cadillac DeVille Concours, DeVille, Eldorado, Seville, and Oldsmobile Aurora models:
Labor Operation Description Labor Time
J6355 Prom, 0.4 hr.
Reprogramming
on Car