1996 Cadillac STS FUEL GAUGE

BOBINO007

MEMBER
1996 CADILLAC STS
V8
FWD
AUTOMATIC
130,000 MILES

I'VE BEEN HAVING PROBLEMS WITH THE ACCURACY OF MY ANALOG FUEL GAUGE ON THE INSTRUMENT PANEL. SOMETIMES IT READS EMPTY AFTER FILLING UP GAS TANK AND REMAINS THAT WAY. SOMETIMES IT READS FULL AND REMAINS THAT WAY EVEN AFTER DRIVING SEVERAL HUNDRED MILES AND SOMETIMES IT STAYS ON HALF TANK EVEN WHEN I KNOW I HAVE ONLY A FEW GALLONS IN TANK. AND VERY RARELY IT READ SOMEWHAT ACCURATE. I BROUGHT VEHICLE TO DEALER. THEY REPLACED FRAYED FUEL PUMP HARNESS'S AND FUEL PUMP ASSEMBLY INCLUDING THE SENDING UNIT. DID NOT FIX PROBLEM. THEN THEY REPLACE THE BODY CONTROL MODULE, THAT THEY CLAIMED WAS MALFUNCTIONING. THIS STILL DID NOT FIX PROBLEM. I LEFT VEHICLE WITH DEALER AGAIN FOR 7 DAYS FOR THEM TO CHECK INSTRUMENT PANEL CLUSTER. THEY CHECKED WIRING AND SAID EVERYTHING IS FINE. I STILL HAVE THE PROBLEM WITH FUEL GAUGE READINGS. CAN YOU PLEASE HELP ME WITH THIS PROBLEM.P.S. IS IT POSSIBLE THE SENDING UNIT WAS INSTALLED INCORRECTLY AND THE FLOAT IS SITTING WRONG INSIDE THE TANK THANK YOU. ROBERT DERISE

1 Reply

MERLIN2021

MECHANIC
17,250 POSTS

Tech bulliten as follows:INACCURATE FUEL GAUGE DISPLAY - UPDATED BCM & PROM TECHNICAL SERVICE BULLETIN Reference Number(s): 63-83-04 Related Ref Number(s): 63-83-04 ARTICLE BEGINNING INACCURATE FUEL GAUGE DISPLAY (INSTALL UPDATED BODY CONTROL MODULE AND PROM) Model(s): 1996 Cadillac Concours, DeVille, Eldorado, Seville Bulletin No.: 8 - Chassis/Body Electrical Section: 63-83-04 Date: March, 1996 MODELS AFFECTED 1996 Cadillac Concours, DeVille, Eldorado, Seville built prior to the following VIN breakpoints: VIN BREAKPOINTS

CONDITION At key on, some owners may comment on an inaccurate fuel level display. The fuel gauge may show full, then slowly return to the proper level. CAUSE This condition may be caused by a Body Control Module (PZM) miscalibration. CORRECTION Install updated Body Control Module (PZM) and PROM, using the following procedure. REMOVE OR DISCONNECT Comfort fuse from the trunk compartment fuse block. 1. Rear seat cushion and seat back. 2. Body Control Module (PZM). 3.INSTALL OR CONNECT Updated PROM into updated Body Control Module (PZM). 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: 5. E = 6 = Eldorado "� K = 4 = Seville "� Ksp = 5 = Concours/DeVille "� 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. 7. PARTS INFORMATION PARTS INFORMATION

NOTE: Parts are currently available from GMSPO. WARRANTY INFORMATION For vehicles repaired under warranty, use: LABOR OPERATION: N4800 LABOR TIME: 0.6 hr.