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Radio Clock - Gains Time

File in Section: 9 - Accessories

Bulletin No.: 63-90-15

Date: November, 1996

Subject:
Radio Clock Gains Time
(Install Updated Body Control Module)

Models:
1996 Cadillac Concours, DeVille, Eldorado and Seville Built Prior to the Following VIN Breakpoints:

Model VIN Breakpoint

Concours/DeVille TU305353
Eldorado TU619572
Seville TU836232

Condition

Some owners of the above listed vehicles may comment that the radio clock may tend to gain time. Up to 2-3 minutes a month may be gained depending on the ambient temperature.

Cause

The clock tuning circuitry in the Body Control Module (PZM) is not precise enough to maintain the required clock accuracy of +/- 1 minute a month.

Correction

Install an updated Body Control Module (PZM) using the following procedure.

Important:
This service part contains an installed PROM. DO NOT OPEN the part as indicated in the Service Manual. This bulletin supersedes the PZM install/connect procedure as indicated on all previous bulletins.

Remove or Disconnect

1. Comfort fuse from the trunk compartment fuse block.

2. Rear seat cushion and seat back.

3. Inspect Body Control Module (PZM).

^ If service part number is 16247212 or 16238499 the PZM has already been updated for this concern and should not be gaining time; reconfirm concern with owner before removing part.

Install or Connect

1. Body Control Module (PZM).

2. Rear seat back and seat cushion.

3. Comfort fuse in trunk compartment fuse block.

4. Reprogram PZM override PZS33 according to the following values:

E = 6 = Eldorado

K = 4 = Seville

KSP = 5 = Concours/DeVille

5. Store value:

^ Hold the front "Defrost" and "Auto/Econ" ("A/C" for analog IPC) for approximately 5 seconds until the display flashes.

6. Cycle ignition.

Parts Information

Description Part Number
Body Control Module (PZM) 16238499

Parts are currently available from GMSPO.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation Description Labor Time
N48OO Computer Use published
(Control), Body labor operation
Replace time.