Alarm goes off by itself
06-23-2013, 06:25 PM
#1
Instructor
Thread Starter
Alarm goes off by itself
99 6 Spd Coupe, 75,000 miles. My car has been acting funny lately. I would find it locked all the time even though I knew I left it unlocked. I have it on a battery tender most of the time. So I drove it Sat about 120 miles. Got home around 9:30pm. Got out of the car and headed in the house. Heard a click and then the lights start flashing and the horn blows. I use the fob and stop the alarm. Open the door and all seems OK. Close the door and start for the house. It does it again. I kept shutting off the alarm but it kept doing it. I noticed that even the radio was coming on. Unhooked hte battery for the night. So I figured the battery was bad. I have no idea how old it is. So I got a Red top Optima today. Put it in and within 5 minutes the same thing again.
I have had other things that needed done and not got back to it. I am going to pull the horn fuse and see if that does anyting.
What else should I look for?
I have had other things that needed done and not got back to it. I am going to pull the horn fuse and see if that does anyting.
What else should I look for?
06-23-2013, 06:41 PM
#3
Tech Contributor
Member Since: Dec 1999
Location: Anthony TX
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
The alarm is controlled by the BCM. The BCM get alarm inputs from the doors and the trunk. The switch for the alarm is inside the door lock and latch mechanism. You will need to see if a door or the trunk switch is malfunctioning
Look in the DIC OPTIONS and if you have a PASSIVE/ACTIVE FOB, make sure that the passive/active option is in the OFF position and the switch on the FOB is off.
Read and post your DTCs and see if you have any:
READING YOUR Engine Diagnostic Trouble Codes (DTC)
This procedure should be carried out any time you experience a problem with your C5. Most inexpensive store bought aftermarket code readers will ONLY read power train DTC’s. Reading the DTC’s with the C5 built in code reader will allow you to read ALL the modules in the vehicle.
The Diagnostic Display Mode is entered with the following procedure:
1) Turn on the ignition but don't start the engine.
2) Press the RESET button to turn off any warning messages. (i.e. door open, trunk open ect)
3) Press and hold the OPTIONS button
4) While holding OPTIONS, press FUEL button four times within a 10 -second period.
Initially, the on-board diagnostics go into an Automatic Mode which will cycle through each module and shows diagnostic codes in a pre-set sequence: PCM - TCS - RTD - BCM - IPC - RADIO - HVAC - LDCM - RDCM - SCM - RFA. All codes will be displayed for each module. ( i.e. PCM = 4 codes) If none are present in a given module, you will see No More Codes on the display.
There are two types of diagnostic codes, Current and History designated with a letter suffix, “C” or “H”. A current code indicates a malfunction is present in the module displaying data. A history code indicates a problem existed sometime in the last 40 or 50 ignition cycles. When not accompanied by a current code of the same number, it's potential evidence of a previous problem, now resolved, that was not removed by clearing the codes. More likely it's an indication of an intermittent malfunction.
Intermittent codes are the most challenging of the diagnostics. An intermittent code may have happened once, may have happened more than once but is inconsistent or may be happening on a regular basis but not at the time the codes are displayed. History codes can also be caused by a current malfunction in a system that is not operating at the time codes are displayed. An example is the rear window defogger which doesn't operate until the Body Control Module detects engine rpm. For history codes set by a module that does not operate with the key on and engine off, a special diagnostic tool called a Scan Tester is necessary to properly diagnose the malfunction.
Once the system has displayed all modules, it goes into the manual mode which allows selection of each module using combinations of Driver Information Center buttons. Manual mode can also be entered during the automatic sequence by pressing any button except E/M. Once the display shows Manual Diagnostics, select a module by pressing the OPTIONS button to go forward or the TRIP button to go back. Once a module is selected, a code is displayed, and if more than one are present; press GAGES to go forward or FUEL to go back.
To exit the diagnostic mode at any time, press E/M. If you want to erase codes in a given module, press RESET To reset the codes once in manual mode, press and hold RESET until it displays NO CODES Press OPTIONS to go to the next module. Repeat the steps until you have reset the codes in all the computer modules.
NOTE!! Only reset the codes IF you want to - it is NOT necessary to do this. Clearing a code does not repair a problem. You are simply erasing the evidence of it in the module's memory. If you clear the code/s, and extinguish the Check Engine Light, your emissions status ready will NOT allow you to pass an emissions test until you have completed the required driving cycles. There are a few body module DTC’s that if set will prevent the module from operating properly. Once the DTC is cleared, the module will return to full function. This is not true for power train DTCs.
If you have never read and cleared your codes, there will probably be a lot of old history DTCs. It is recommended that you clear your codes and see if any come back during a driving cycle. Those are the ones that you need to concentrate on diagnosing.
Once you have the codes, the next question is: What to do with the information?
First, consult the factory service manual. Any serious C5 Do-It-Yourself owner should invest in the Corvette Service Manual of the appropriate model year. The Service Manual is really a requirement if you want to understand and work on your C5.
NOTE and a WARNING. You can read the DTCs while the engine is running. I pull mine up all the time while driving.
WARNING. Don’t become distracted while reading DTCs while your driving and cause an accident!!!!! Use common sense and drive safe.
These are some very good C5 Diagnostic Trouble Code (DTC) explanation web sites!!! They also explain how to read the DTCs
Here are some very good sites that explain what DTC mean:
http://www.gearchatter.com/viewtopic11755.php
http://www.obd-codes.com/trouble_cod...d-ii-codes.php
Make sure to include the H or C suffix when you post your DTCs!!
Bill
Look in the DIC OPTIONS and if you have a PASSIVE/ACTIVE FOB, make sure that the passive/active option is in the OFF position and the switch on the FOB is off.
Read and post your DTCs and see if you have any:
READING YOUR Engine Diagnostic Trouble Codes (DTC)
This procedure should be carried out any time you experience a problem with your C5. Most inexpensive store bought aftermarket code readers will ONLY read power train DTC’s. Reading the DTC’s with the C5 built in code reader will allow you to read ALL the modules in the vehicle.
The Diagnostic Display Mode is entered with the following procedure:
1) Turn on the ignition but don't start the engine.
2) Press the RESET button to turn off any warning messages. (i.e. door open, trunk open ect)
3) Press and hold the OPTIONS button
4) While holding OPTIONS, press FUEL button four times within a 10 -second period.
Initially, the on-board diagnostics go into an Automatic Mode which will cycle through each module and shows diagnostic codes in a pre-set sequence: PCM - TCS - RTD - BCM - IPC - RADIO - HVAC - LDCM - RDCM - SCM - RFA. All codes will be displayed for each module. ( i.e. PCM = 4 codes) If none are present in a given module, you will see No More Codes on the display.
There are two types of diagnostic codes, Current and History designated with a letter suffix, “C” or “H”. A current code indicates a malfunction is present in the module displaying data. A history code indicates a problem existed sometime in the last 40 or 50 ignition cycles. When not accompanied by a current code of the same number, it's potential evidence of a previous problem, now resolved, that was not removed by clearing the codes. More likely it's an indication of an intermittent malfunction.
Intermittent codes are the most challenging of the diagnostics. An intermittent code may have happened once, may have happened more than once but is inconsistent or may be happening on a regular basis but not at the time the codes are displayed. History codes can also be caused by a current malfunction in a system that is not operating at the time codes are displayed. An example is the rear window defogger which doesn't operate until the Body Control Module detects engine rpm. For history codes set by a module that does not operate with the key on and engine off, a special diagnostic tool called a Scan Tester is necessary to properly diagnose the malfunction.
Once the system has displayed all modules, it goes into the manual mode which allows selection of each module using combinations of Driver Information Center buttons. Manual mode can also be entered during the automatic sequence by pressing any button except E/M. Once the display shows Manual Diagnostics, select a module by pressing the OPTIONS button to go forward or the TRIP button to go back. Once a module is selected, a code is displayed, and if more than one are present; press GAGES to go forward or FUEL to go back.
To exit the diagnostic mode at any time, press E/M. If you want to erase codes in a given module, press RESET To reset the codes once in manual mode, press and hold RESET until it displays NO CODES Press OPTIONS to go to the next module. Repeat the steps until you have reset the codes in all the computer modules.
NOTE!! Only reset the codes IF you want to - it is NOT necessary to do this. Clearing a code does not repair a problem. You are simply erasing the evidence of it in the module's memory. If you clear the code/s, and extinguish the Check Engine Light, your emissions status ready will NOT allow you to pass an emissions test until you have completed the required driving cycles. There are a few body module DTC’s that if set will prevent the module from operating properly. Once the DTC is cleared, the module will return to full function. This is not true for power train DTCs.
If you have never read and cleared your codes, there will probably be a lot of old history DTCs. It is recommended that you clear your codes and see if any come back during a driving cycle. Those are the ones that you need to concentrate on diagnosing.
Once you have the codes, the next question is: What to do with the information?
First, consult the factory service manual. Any serious C5 Do-It-Yourself owner should invest in the Corvette Service Manual of the appropriate model year. The Service Manual is really a requirement if you want to understand and work on your C5.
NOTE and a WARNING. You can read the DTCs while the engine is running. I pull mine up all the time while driving.
WARNING. Don’t become distracted while reading DTCs while your driving and cause an accident!!!!! Use common sense and drive safe.
These are some very good C5 Diagnostic Trouble Code (DTC) explanation web sites!!! They also explain how to read the DTCs
Here are some very good sites that explain what DTC mean:
http://www.gearchatter.com/viewtopic11755.php
http://www.obd-codes.com/trouble_cod...d-ii-codes.php
Make sure to include the H or C suffix when you post your DTCs!!
Bill
Last edited by Bill Curlee; 06-23-2013 at 06:44 PM.
06-26-2013, 08:06 PM
#4
Instructor
Thread Starter
Latest
Checked codes. All were History and voltage related.
B2573H, B2583H, B2282H, B2283H, B2284H, B2285H, U1016H, U1064H, U1096H, U1255H.
Cleared all out. Started car. ran for enough time to get 180F. Shut down and it does almost OK. I still get a sound (like a solenoid) and the interior lights come on for a while and the car locks itself. Now today I ran it long enough to get warm again. I still got the interior lights coming on and timing out, but so far it has not locked itself and no alarm. I also added my CTEK maintainer.
I am wanting to think my 'old' battery was bad and messing with the voltage. Putting the new one in, I should have ran it longer and charged it up more. So, I don't know if I am out of the woods yet, but will wait and see.
B2573H, B2583H, B2282H, B2283H, B2284H, B2285H, U1016H, U1064H, U1096H, U1255H.
Cleared all out. Started car. ran for enough time to get 180F. Shut down and it does almost OK. I still get a sound (like a solenoid) and the interior lights come on for a while and the car locks itself. Now today I ran it long enough to get warm again. I still got the interior lights coming on and timing out, but so far it has not locked itself and no alarm. I also added my CTEK maintainer.
I am wanting to think my 'old' battery was bad and messing with the voltage. Putting the new one in, I should have ran it longer and charged it up more. So, I don't know if I am out of the woods yet, but will wait and see.