For 1990-2009 cars

# Info - The Year 2000 (Y2K) and Vehicle Electronics

Subject: | The Year 2000 (Y2K) and Vehicle Electronics

Models: | 2000 and Prior Passenger Cars and Trucks

One of GM's first priorities in its Year 2000 Program was the analysis of vehicle electronics in GM passenger cars and trucks. This review included all current and planned models, as well as older cars and trucks produced during the period of approximately the last 15 years, back to when GM first began to install microprocessors capable of processing date-related information.

Most of the electronic systems in GM vehicles have no date-related functionality and, therefore, pose no Year 2000-related concerns. Those few systems that have date-related functionality were found to be Year 2000 ready. Accordingly, GM anticipates that there will be no problems with past, current, or future model vehicles as a result of calendar Year 2000 (Y2K).

Nonetheless, it is possible that some customers will report concerns on their vehicles on or after January 1, 2000 that they believe are related to calendar Year 2000 (Y2K). This bulletin is intended to assist dealers in explaining to those customers why their concerns are not related to calendar Year 2000 (Y2K). However, in the event that dealership service personnel believes that a reported concern is possibly related to calendar Year 2000 (Y2K), they should report it to the Technical Assistance Center (TAC) during normal business hours, in accordance with the normal reporting procedure, and await further direction.

#### Microprocessors and Display Device Dates

Some common examples of on-board vehicle microprocessors include the powertrain control module, the ABS controller, automatic climate control controller, supplemental restraint system (air bag) controller , and the keyless remote entry controller. These microprocessors do not process calendar date data. As such, they are unaffected by the Y2K issue. No on-board vehicle microprocessor that controls fundamental vehicle operation like powertrain, braking, suspension, steering, fuel delivery, exhaust, base electrical (including engine cranking and battery charging), windshield wipers, restraints and the like, has calendar date processing capability. Consequently, the Y2K issue affects none of these vehicle systems.

Examples of on-board vehicle microprocessors and display devices that may process and display calendar date data are the Onstar System electronics, Driver Information Centers, and some body control modules (BCMs).

The Onstar System receives date data from satellite transmission, and communicates it to the ground tracking station. The Onstar System in-vehicle electronics have been tested and determined to be Year 2000 ready.

Some BCMs process calendar dates. Vehicles with these BCMs are readily identified as having calendar date displays in the Driver Information Center or elsewhere displayed in the instrument panel. If the vehicle does not have a calendar date display visible, it is very unlikely to have a calendar date processing BCM aboard. A vehicle with calendar date processing capability will have a calendar date entry device easily set by the user as described in that vehicle's Owner's Manual. BCMs with calendar date processing ability do so only for user convenience reasons like displaying the date, computing estimated time of arrival with the trip computer, alerting when an oil change is recommended, etc. As such, they do not influence the vehicle's fundamental ability to operate. Known date processing BCMs have been analyzed and determined to be Year 2000 ready.

#### Handling of Incorrect Display Device Dates

If a customer vehicle displays an incorrect date on the display device, the procedure in the vehicle Owner's Manual describing how to set the correct date should be followed. If the display device is not working, consult the Service Manual. If further diagnosis is needed, contact TAC.

#### After-Market Equipment

This information applies only to GM factory installed equipment. GM makes no representation whatsoever about the Y2K readiness of after-market equipment installed on any vehicle.

This information is intended to help dealership service personnel respond to customer concerns regarding the impact of calendar Year 2000 (Y2K) on their GM passenger car or truck. It is not intended to modify, or in any way alter or extend a vehicle's warranty.