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Home >> Cadillac >> 1990 >> Allante F7/ME9 >> Repair and Diagnosis >> External Pages >> Different car >> Section 20 (Body Computer Module) >> Self-Diagnostic System >> Diagnostic Trouble Code Definitions
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Diagnostic Trouble Code Definitions

WARNING: This page is about a different car, the 1988 Cadillac Allante and 1987 Cadillac Allante. However, it is still accessible from the selected car via links, so may be relevant.
BCM DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC Description Go To
B110 Outside Temperature Sensor Circuit (1)
B111 A/C High Side Temperature Sensor Circuit (1)
B112 A/C Low Side Temperature Sensor Circuit (1)
B113 In-Car Temperature Sensor Circuit (1)
B115 Sunload Sensor Circuit (1)
B119 Twilight Photocell Circuit DTC B119 
B120 Twilight Delay Pot Circuit DTC B120 
B120 & B122 Twilight Delay Panel Dimming Switch DTC B120 & B122 
B122 Panel Lamp Dimming Pot Failure (2)
B124 Vehicle Speed Sensor DTC B124 
B127 PRND321 Sensor (2)
B132 Oil Pressure Sensor Failure (2)
B334 Loss Of ECM Data DTC B334 
B335 Loss Of CCDIC Data DTC B335 
B336 Loss Of IPC Data DTC B336 
B337 Loss Of HVAC Programmer Data DTC B337 
B409 Charging System Fault (3)
B410 Regulator Fault (3)
B411 Or B412 Battery Voltage Too Low Or Too High (3)
B420 BCM Output Driver No. 1 DTC B420 
B421 BCM Output Driver No. 2 DTC B421 
B440 Air Mix Valve (Door) Circuit Problem (1)
B441 Cooling Fans (1)
B446 Or B447 Low Refrigerant Charge (1)
B448 Low Refrigerant Pressure (1)
B446, B447 Or B448 Refrigerant System Problem (1)
B449 A/C HI Temp (1)
B450 Coolant HI Temp - A/C (1)
B480 Anti-Lock Data Problem (4)
B481 Anti-Lock Fault (4)
B552 BCM Memory Reset DTC B552 
B556 EEPROM DTC B556 
(1) Perform appropriate test in AUTOMATIC A/C-HEATER SYSTEMS article in HVAC.
(2) Perform appropriate test in INSTRUMENT PANELS article in ACCESSORIES & ELECTRICAL.
(3) Perform appropriate test in GENERATORS & REGULATORS article in ELECTRICAL.
(4) Perform appropriate test in ANTI-LOCK -- BOSCH III -- ALLANTE article in BRAKES.
LIGHTING DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC Description
L010  Redundant Taillamp Relay
L011  Redundant Headlamp Relay
L110  Headlight Switch Communication Failure
L202  OSM No. 2 Communication Failure
L203  OSM No. 3 Communication Failure
L204  OSM No. 4 Communication Failure
L205  OSM No. 5 Communication Failure
L206  OSM No. 6 Communication Failure
L207  OSM No. 7 Communication Failure
L208  OSM No. 8 Communication Failure
L209  OSM No. 9 Communication Failure
L210  OSM No. 10 Communication Failure
L302 OSM No. 2 Output Failure
L303 OSM No. 3 Output Failure
L304 OSM No. 4 Output Failure
L305 OSM No. 5 Output Failure
L306 OSM No. 6 Output Failure
L307 OSM No. 7 Output Failure
L308 OSM No. 8 Output Failure
L309 OSM No. 9 Output Failure
L310 OSM No. 10 Output Failure
L411 Lighting System Low Voltage Warning
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