REVISED DIGITAL CLUSTER (U2A) (SERVICE INFORMATION)

SUBJECT REVISED DIGITAL CLUSTER U2A INFORMATION

MODELS/YEARS 1991-92 NINETY EIGHT AND 1992 EIGHTY EIGHT -----------------------------------------------------------------------------

This bulletin cancels and replaces Service Manual Update 92-U-03. Please discard SMU 92-U-03. Use the revised diagnostic chart below to correct a metric only display problem on affected domestic (U.S.) vehicles.

INSTRUMENT CLUSTER SYMPTOM DIAGNOSIS ------- ------- ---------

ANALOG (U2E) HVAC Programmer displays 1. Check HVAC Programmer external or set temperature connector terminal C6 for a in degrees Celsius BLK wire. If a wire is present, cut it, tape ends to prevent shorts, and then tape it back to wiring harness. If wire is not present, replace HVAC Programmer. -----------------------------------------------------------------------------

GAGES (UB7) IPC E/M button does not 1. Disconnect Instrument Cluster change HVAC Programmer connector C1. Put Ignition temperature display between Switch in RUN, turn on Air F and C; but button does Conditioning, and observe HVAC change DIC information Temperature. between English and metric values. - If temperature is in F, go to step 2.

- If temperature is in C, check LT BLU (81 1) wire for a short to ground. Also check that export ground, BLK (154) wire, --------------------------------------------- has not been included at termi- DIGITAL (U2A) IPC E/M button does not nal C6 of HVAC Programmer. change HVAC Programmer tem- perature display between F - If a wire is present, cut it, and C; but button does change tape ends to prevent shorts, both IPC gages and DIC infor- and then tape it back to wiring mation between English and harness. Also check continuity Metric values. between HVAC Programmer connector terminal C6 and IPC E/M button does not change Instrument Cluster connector C1 HVAC Programmer temperature terminal A3. If an open circuit display between F and C, or IP is found, install a .5 LT BLU Gages between English and wire between the two terminals metric values; but button does using Terminal Repair Kit change DIC information between J 38125-A. English and metric values. 2. With Ignition Switch in RUN, connect a fused jumper between Instrument Cluster connector C1 terminal A3 and ground. Observe HVAC display.

- If temperature is displayed in C, replace Instrument Cluster.

- If temperature is not displayed in C, check LT BLU (811) wire for an open between HVAC Programmer connector terminal C6 and Instrument Cluster connector C1 terminal A3. Repair as necessary. If OK, replace HVAC Programmer. ------------------------------------------------------------------------------

GAGES(UB7) or IPC E/M button does not 1. Replace instrument Cluster. DIGITAL (U2A) change DIC information between English and metric values.

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.