For 1990-2009 cars

# UNWANTED METRIC DISPLAY POSSIBLE SHORT TO GROUND

#### MODELS AFFECTED: 1985-1987 DE VILLE, FLEETWOOD 1980-1987 RWD DE VILLES AND BROUGHAMS 1980-1985 ELDORADO, SEVILLE

Some vehicles built for use in the United States may exhibit a condition of unwanted metric display. This condition may be due to a short to ground on the Metric select circuit (circuit 911 on 1982-1983 vehicles and circuit 811 on 1984-1987).

On vehicles equipped with a digital cluster, the digital cluster provides a ground, via the metric select circuit, for either the Electronic Climate Control (ECC) head, the ECM or BCM when metric displays are selected.

On vehicles equipped with an analog cluster, the metric select circuit originates from either the ECC head, the ECM or BCM and terminates in an unused single cavity connector in the lower left-hand side of the instrument panel. There is no way to convert back and forth between metric and English displays on a vehicle with an analog cluster.

To repair the condition of unwanted metric displays, follow the procedures outlined below.

HT4100 -Transverse (De Ville & Fleetwood Only), 4.3L Diesel 1985-1987

Cluster: Back-out the light blue wire from pin 13 of the black BCM connector Digital and from pin E of the digital cluster connector. Check for a short to ground on this circuit and repair if one is present. If no short is found, with the wire still backed-out, power-up the displays (key on) and see if it is still in metric. If so, replace the BCM. If not, send the digital cluster out for repair.

Cluster: Back-out the light blue wire from pin 13 of the black BCM Analog connector. Check for a short to ground on this circuit and repair if one is found. If no short is found, with the wire still backed-out from the BCM, power-up the displays (key on) and see if it is still in metric. If so, replace the BCM.

HT4100 - Longitudinal 1982-1983

Cluster: Back-out the black wire from pin 5 of the red ECM connector and from pin H of the digital cluster. Check for a short to ground on this wire and repair if one is present. If no short is found with the wire still backed out, power-up displays (key-on) and see if it is still in metric. If so, replace the ECM. If not, replace the digital cluster.

Cluster: Back-out the black wire from pin 5 of the red ECM connector. Check Analog for a short to ground on this wire and repair if one is present. If no short is found with the wire still backed out, power-up the displays (key on) and see if it is still in metric. If so, replace the ECM.

HT4100 - Longitudinal 1984-1985

Cluster: Back-out the light blue wire from pin 5 of the red ECM connector and from pin E of the digital cluster connector. Check for a short to ground on this circuit and repair if one is present. If no short is found, with the wire still backed-out, power-up the displays (key on) and see if it is still in metric. If so, replace the ECM. If not, send digital cluster out for repair.

Cluster: Back-out the black wire from pin C of the Electronic Climate Analog Control Panel. Check for a short to ground on this wire and repair if one is present. If no short is found, with the wire still backed-out, power-up the displays (key on) and see if it is still in metric. If so, replace the ECC panel.

5.7L Diesel, 5.OL Gas, 4.1 L V-6 1980-1987

Cluster: Back-out the black wire from pin C of the Electronic Climate Digital Control Panel and from pin H of the digita l cluster. Check for a short to ground on this wire and repair if one is present. If no short is found, with the wire still backed-out, power-up the displays (key on) and see if it is still in metric. If so, replace the ECC panel. If not, replace the digital cluster.

Cluster: Back-out the black wire from pin C of the Electronic Climate Analog Control Panel. Check for a short to ground on this wire and repair if one is present. If no short is found, with the wire still back out, power-up the displays (key on) and see if it is still in metric. If so, replace the ECC panel.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.