GM Service Manual Online
For 1990-2009 cars only

ECC CONTROL HEAD NO DECIMAL DESCRIPTION NORMAL OPERATION

THE ELECTRONIC CLIMATE CONTROL (ECC) CONTROL HEAD ON EARLY PRODUCTION 1982 CADILLACS MAY NOT DISPLAY ONE OR BOTH DECIMAL POINTS. WHEN PERFORMING DFI DIAGNOSTICS, A "-1.8.8" SHOULD NORMALLY APPEAR ON THE ECC DISPLAY AS A SEGMENT CHECK. THE ECC CONTROL HEAD SHOULD NOT BE REPLACED FOR JUST AN INOPERATIVE DECIMAL POINT. IF ANY OTHER SEGMENTS ARE INOPERATIVE, THE ECC CONTROL HEAD SHOULD BE REPLACED BEFORE CONTINUING WITH DFI DIAGNOSIS SINCE AN IMPROPER CODE DISPLAY COULD LEAD TO MISDIAGNOSIS.

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.