Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Engine Controls - MIL Function During I/M Testing
1999 Buick LeSabre V6-3.8L VIN KSECTION Engine Controls - MIL Function During I/M Testing
Bulletin No.: 06-06-04-037
Date: August 04, 2006
INFORMATION
Subject:
Normal Characteristics of Malfunction Indicator Lamp (MIL) During On-Board Diagnostic (OBD) Inspection/Maintenance (I/M) Testing
Models:
2007 and Prior Passenger Cars and Trucks (Including Saturn)
2007 and Prior HUMMER H2, H3
2007 and Prior Saab 9-7X
The purpose of this bulletin is to inform dealers and OBD inspection/maintenance testing facilities of normal characteristics of the malfunction indicator lamp (MIL) and the engine or powertrain control module (ECM or PCM).
Some customers may comment on having been rejected or having failed an OBD emission inspection. In some cases, these vehicles do not need repair and may have been rejected or may have failed the OBD emission inspection due to a lack of understanding with regard to the normal characteristics of the MIL and ECM/PCM.
Following an engine run period, the MIL may not illuminate on an ignition OFF to ignition ON transition unless a 30 second delay is observed between key OFF and key ON. The delay is necessary on some control modules to allow the control module, either ECM or PCM, to power down. Most vehicles may require less time to achieve power down, but a 30 second delay will satisfy all known applications. This is normal operation for all GM control modules.
Some OBD I/M emissions test centers may not wait 30 seconds after a vehicle is turned off before proceeding with the MIL bulb check, which could result in a vehicle rejection or test failure.
To confirm proper MIL operation, wait 30 seconds after the ignition is turned OFF before proceeding with any key ON bulb check.

Disclaimer
Date: August 04, 2006
INFORMATION
Subject:
Normal Characteristics of Malfunction Indicator Lamp (MIL) During On-Board Diagnostic (OBD) Inspection/Maintenance (I/M) Testing
Models:
2007 and Prior Passenger Cars and Trucks (Including Saturn)
2007 and Prior HUMMER H2, H3
2007 and Prior Saab 9-7X
The purpose of this bulletin is to inform dealers and OBD inspection/maintenance testing facilities of normal characteristics of the malfunction indicator lamp (MIL) and the engine or powertrain control module (ECM or PCM).
Some customers may comment on having been rejected or having failed an OBD emission inspection. In some cases, these vehicles do not need repair and may have been rejected or may have failed the OBD emission inspection due to a lack of understanding with regard to the normal characteristics of the MIL and ECM/PCM.
Following an engine run period, the MIL may not illuminate on an ignition OFF to ignition ON transition unless a 30 second delay is observed between key OFF and key ON. The delay is necessary on some control modules to allow the control module, either ECM or PCM, to power down. Most vehicles may require less time to achieve power down, but a 30 second delay will satisfy all known applications. This is normal operation for all GM control modules.
Some OBD I/M emissions test centers may not wait 30 seconds after a vehicle is turned off before proceeding with the MIL bulb check, which could result in a vehicle rejection or test failure.
To confirm proper MIL operation, wait 30 seconds after the ignition is turned OFF before proceeding with any key ON bulb check.
Disclaimer
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.