Cadillac OBD/OBD2 Codes >> 91-92 Brougham 5.0 VIN E & 5.7L VIN 7

1991-1992 Cadillac Brougham


Accessing Trouble Codes

Without using A/C control panel
  • Access data link connector (DLC)
  • Jump data link connector (DLC) terminals A and B Image 1
  • Switch ignition ON. Do NOT start engine.
  • Count MIL flashes.  Note trouble codes. Compare with trouble code table.
  • Firstly trouble code 12 will be displayed 3 times
  • Trouble codes consist of 2 groups, displayed as follows:
    • First group indicates the ‘tens’ of the trouble code
    • Second group indicates the ‘units’ of the trouble code
    • A short pause separates each group
    • A long pause separates each trouble code
    • For example: Trouble code 12 displayed. Start of diagnosis.
  • Each additional trouble code will now be displayed 3 times, in ascending order

NOTE: If no additional trouble codes are stored, code 12 will continue to be displayed

Using A/C control panel
  • Switch ignition ON.
  • Simultaneously press and hold the A/C control panel ‘OFF’ and ‘Warmer’ buttons Image 3 [1] & [2]
  • When all segments of the display  Image [3] illuminate: Release the A/C control panel ‘OFF’ and ‘Warmer’ buttons
  • Parameter number ‘-00’ (A/C codes) will be displayed  Image [3]
  • Press and release the ‘HI’ button  Image [4]
  • Parameter number ‘-01’ (ECM codes) will be displayed
  • Press and release the ‘HI’ button
  • Display will alternate between ECM parameter number ‘-01’ and the trouble code at 1.6 second intervals
  • Trouble codes will be displayed in ascending order
  • Cycle will be repeated after all ECCM trouble codes have been displayed
  • If no ECM trouble codes are stored, trouble code ’00’ will be displayed
NOTE: All ECM codes start with the parameter number ‘-01’.
  • To end diagnosis:
    • Press the ‘AUTO’ button or switch ignition OFF for 10 seconds

Clearing Trouble Codes

Without using A/C control panel
  • Ensure ignition switched OFF.
  • Disconnect battery ground cable for 30 seconds
  • Reconnect battery ground cable
  • Repeat checking code procedure to ensure no trouble codes remain in ECM fault memory
  • Trouble codes can also be erased by using a Scan Tool connected to the data link connector (DLC)
Using A/C control panel
  • Access ECM trouble codes
  • During trouble code display:
  • Simultaneously press and hold ‘OFF’ and ‘LO’ buttons Image 3 [1] & [6]
  • When ’00’ is displayed:
    • Release the ‘OFF’ and ‘LO’ buttons
  • To end diagnosis:
    • Press the ‘AUTO’ button Image 3 [5], or switch ignition OFF for 10 seconds

Cadillac Brougham BCM and PCM Codes and Diagnostic Procedures


Diagnostics Basic Operation





Enter self diagnostics by simultaneously pressing and holding the “OFF” and “WARMER” buttons on the Electronic Climate Control panel until the automatic segment check begins.
2Malfunction codes are displayed in the following order:..- ECC current codes ( parameter number -00 )1..- ECC history codes ( parameter number -00 )
3To select a specific parameter, press “HI” to increment and “LO” to decrement the parameter number.
4After the status light display begins, ECC error codes are displayed.  PCM codes may be displayed by selection parameter -01 and then pressing the “OUTSIDE TEMP” button.
5Exit diagnostics by pressing the “AUTO” button
6Pressing “OUTSIDE TEMP” switches between parameter number and parameter data
7To over-ride a program number, while in program number display, parameter -11, pressing “WARMER” or “COLDER” will increase or decrease the program number.

Parameter Number -00


ECC Diagnostic Codes

00No ECC system fault
10Out-side ambient temp sensor malfunction
12A/C evaporator inlet temp sensor malfunction
13In-car tem sensor malfunction
19Blower motor failure
32PCM-ECC data problem
40Air mix valve problem
48Very low refrigerant pressure level
49High engine temp
50EVO system fault

Parameter Number -01


PCM Diagnostic Codes

00No PCM faults
12No engine RPM References pulses
13Oxygen sensor circuit fault
14Shorted coolant sensor circuit fault
15Open coolant sensor circuit fault
21Open throttle position sensor circuit fault
22Shorted throttle position sensor circuit fault
23Open MAT sensor circuit fault
24VSS circuit fault
25Shorted MAT sensor circuit fault
32EGR system fault
33Open MAP sensor circuit fault
34Shorted MAP sensor circuit fault
42EST/bypass circuit fault
43ESC failure
44Lean O2 signal
45Rich O2 signal
51PROM error
52Backup fuel cal-pack missing
54Fuel pump relay malfunction
55A/D Converter malfunction


-00ECC fault codes00-150Code
-01PCM fault codes00-55Code
-02Program number0-255Counts
-03IAC motor position0-255Counts
-07Oxygen sensor Volts
-08MAT C
-10Ignition voltage9.0-16.0Volts
-11Program number0-100%
-12Vehicle speed0-199MPH
-19Actual blower voltage-3.3-18Volts
-20Commanded blower voltage-3.3-18Volts
-21Engine coolant temp-40-151C
-22Commanded blend door position0-255Counts
-23Actual blend door position0-255Counts
-24Air delivery mode0-6Code
-25In-car temp-40-102C
-26Outside air temp-40-93C
-28Evaporator inlet temp-40-93C
-30Ignition cycle counter0-99Counts
-31PROM ID0-9999Code


Air Delivery Mode

0Max A/C
5Blower delay