Question about 1991 Buick Riviera

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I purchased a 91 riviera 79,450 mi.battery would go dead after sitting for 3 or 4 days it has a flashing security light on the dash but was told that is not the problem.We did a voltage test and it read 4.67 to 4.25 volts we disconnected the new radio, power antenna, and new remote starting system still 4.50 to 4.67 fluxuating. unpluged different modules under dash one was BCM or ECM voltage dropped to .04 to.09 fluxuation.that is where it is at now with everything installed do I need to purchase a new unit. Thank you in advance for any help you can render.

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  • funtimesb4u Feb 01, 2009

    I have a new 1000 amp battery in the vehicle now my problem is the vehicle in only suppost to draw .04 volts when parked but was drawing 4.25 to 4.67 volts parked we did some work and managed to regulate it down to .04 to .09 volts and fluxuates between those numbers. Should I replace the ECM unit or what

  • funtimesb4u Feb 16, 2009

    Solved problem BCM

  • funtimesb4u Feb 16, 2009

    Solved Problem BCM or ECM unit for some reason was drawing the AMPS we unpluged the unit and the power drain dropped to .04 to .09 this is acceptable have had no more problem with the battery going dead after it sat a week.



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These cars pull alot of power. My Aunt car done the same thing, and it was the same car. Need to buy a new battrey with alot of Cold cranking AMP's. This should fix the problem.

Posted on Jan 31, 2009

  • spankie09 Feb 01, 2009

    If you have made the ajustments already. I would ride it out a few days to see if this makes the problem go away.



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This code will flash indefinitely if there are no stored trouble codes. If codes are stored in memory, Code 12 will flash three times before the next code appears. Codes are displayed in the next highest numerical sequence. For example, Code 13 would be displayed next if it was stored in memory and would read as follow: flash, pause, flash, flash, flash, long pause, repeat twice. This sequence will continue until all codes have been displayed, and then start all over again with Code 12. CLEARING CODES (EXCEPT CADILLAC) Except Riviera, Toronado and Trofeo: To clear any Diagnostic Trouble Codes (DTC's) from the PCM memory, either to determine if the malfunction will occur again or because repair has been completed, power feed must be disconnected for at least 30 seconds. Depending on how the vehicle is equipped, the system power feed can be disconnected at the positive battery terminal pigtail, the inline fuse holder that originates at the positive connection at the battery, or the ECM/PCM fuse in the fuse block. The negative battery terminal may be disconnected but other on-board memory data such as preset radio tuning will also be lost. To prevent system damage, the ignition switch must be in the OFF position when disconnecting or reconnecting power. When using a Diagnostic Computer such as Tech 1, or equivalent scan tool to read the diagnostic trouble codes, clearing the codes is done in the same manner. On some systems, OTC's may be cleared through the Tech 1, or equivalent scan tool. On Riviera, Toronado and Trofeo, clearing codes is part of the dashboard display menu or diagnostic routine. Because of the amount of electronic equipment on these vehicles, clearing codes by disconnecting the battery is not recommended. Riviera, Toronado and Trofeo (Non-CRT/DID Vehicles) — Using The On-Board Diagnostic Display System: First turn the ignition to theON position. On Riviera depress the OFF and TEMP buttons on the ECCP at the same time and hold until all display segments light. This is known as the Segment Check. On Toronado and Trofeo follow the same procedure, however, depress the OFF and WARMER buttons on the ECOP instead. After diagnostics is entered, any OTC's stored in computer memory will be displayed. Codes may be stored for the PCM, BCM, PC or SIR systems. Following the display of OTC's, the first available system for testing will be displayed. For example, 'EC?' would be displayed on Riviera for EOM testing, while on Toronado and Trofeo the message 'ECM?' will appear. The message is more clear on these vehicles due to increased character space in the IPO display area.
  1. Depress the 'FAN UP' button on the ECCP until the message 'DATA EC?' appears on the display for Riviera, or 'ECM DATA?' is displayed on Toronado and Trofeo.
  2. Depress the 'FAN DOWN' button on the ECCP until the message 'CLR E CODE' appears on the display for Riviera, or 'ECM CLEAR CODES?' is displayed on Toronado and Trofeo.
  3. Depressing the 'FAN UP' button on the ECCP will result in the message 'E CODE CLR' or 'E NOT CLR' on Riviera, 'EOM CODES CLEAR' or 'ECM CODES NOT CLEAR' on Toronado and Trofeo. This message will appear for 3 seconds. After 3 seconds the display will automatically return to the next available test type for the selected system. It is a good idea to either cycle the ignition once or test drive the vehicle to ensure the code(s) do not reset. Toronado and Trofeo (CRT/DID Equipped) — Using The On-Board Diagnostic Display System: First turn the ignition switch to theON position. Depress the 'OFF' hard key and 'WARM' soft key on the CRT/DID at the same time and hold until all display segments light. This is the 'Segment Check.' During diagnostic operation, all information will be displayed on the Driver Information Center (DIC) located in the Instrument Panel Cluster (IPC). Because of the limited space available single letter identifiers are often used for each of the major computer systems. These are: E for ECM, B for 6CM, I for IPC and R for SIR. After diagnostics is entered, any OTC's stored in computer memory will be displayed. Codes may be stored for the PCM, BCM, PC or SIR systems. Following the display of OTC's, the first available system for testing will be displayed. This will be displayed as 'ECM?'.
  4. Depress the 'YES' soft key until the display reads 'ECM DATA?'.
  5. Depress the 'NO' soft key until the display reads 'ECM CLEAR CODES?'.
  6. Depressing the 'YES' soft key will result in either the message 'ECM CODES CLEAR' or 'ECM CODES NOT CLEAR' being displayed, indicating whether or not the codes were successfully cleared. This message will appear for 3 seconds. After 3 seconds the display will automatically return to the next available test type for the selected system. It is a good idea to either cycle the ignition once or test drive the vehicle to ensure the code(s) do not reset.

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