Sierra 1500 2WD V8-5.3L Hybrid (2004)
Oil Pressure Warning Lamp/Indicator: All Technical Service Bulletins
Engine Controls - Low Oil Pressure Message/Warning Chime
Bulletin No.: 05-08-49-026
Date: October 28, 2005
TECHNICAL
Subject:
Low Oil Pressure Message Display and Chimes Activated While Driving Following Hybrid (HP2) LM7 Engine Auto-Start (Reprogram the PCM)
Models:
2004-2005 Chevrolet Silverado Hybrid Truck (HP2) Models
2004-2005 GMC Sierra Hybrid Truck (HP2) Models
with Vortec 5.3L V-8 Engine VIN T - RPO LM7) and 4L60-E Hybrid (M33) Transmission
Condition
Some customers may comment that the Driver Information Center (DIC) displays a "low oil pressure" message and chimes are activated while driving.
This condition will usually occur immediately following a hybrid engine auto-start.
Cause
The low oil pressure diagnostic only waits 2 seconds after a hybrid auto-start to flag a failure. The auto-start does not have an engine rpm flare like
normal key crank starts and the oil pressure can sometimes normally take longer than 2 seconds to reach the calibrated pressure level.
Correction
The low oil pressure diagnostic calibration time was increased to 12 seconds. The revised diagnostic will monitor the oil pressure for 12 seconds prior to
sending a failure message. An updated PCM calibration will be available to dealerships as part of TIS 2000 incremental satellite update version 11.0
(NAO version 25.010) or greater. As always, make sure your Tech 2(R) is updated with the latest software version.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
