1996 993 key remote does not work
#16
Burning Brakes
I got one from ecu doctors as well and I do notice the range has improved about 5 feet. Considering the original range was more like 3 feet, and now with the ecu doctors remote an additional 5 feet for a total of 8 feet, technically, it is a significant improvement.
#17
RL Community Team
Rennlist Member
Rennlist Member
Before throwing good money on the issue. The fob battery may still be no good. Buy a new one and check it that it is not new old stock. Also disconnect your car's battery and reconnect it to reboot the system before going the high dollar route. Clean the battery connections on your fob. I would buy a 2nd new fob first and mate it to your car then in sequence remate your existing fob. If, when and how the mating process fails will give away if your problem is with the fob or the system in the car.
#18
Rennlist Member
I would also attempt to re-pair the fob with the unit before getting a whole new unit. If something at the fob has changed the signal characteristics, or something on the unit has changed how the signal is received, the fob may "look" different to the unit than previously, which would exhibit the "light's on, no one's home" symptoms. A re-pair may buy you a bit more time.
#20
Thanks for comment...
It doesn’t seem like the fob is communicating at all with the car. No clicks, nothing. My car is essentially dead until I figure this out. Is the CLM embedded in immobilizer or a separate unit that can be changed independently?
To be thorough, I’ll buy new fob batteries and check car battery voltage today.
Thanks again.
That ECU is very reliable and rarely if ever fails, except when water damage occurs or voltage problems.
#21
Burning Brakes
Loren - Is the fuse in the unit itself? Does the seat need to be removed to access?
#22
Burning Brakes
I changed the fob battery with a new one (measured it at 1.5 volts, so it was good) and cleaned the contacts. No difference; The car completely ignored the fob.
I then removed the car battery and cleaned the terminals with a wire brush. While the battery is almost 9 years old, and I’ll probably buy a new one, it did measure at almost 13 volts when I reinstalled it fresh from a short hookup with the battery tender. Tightened everything up, installed the key into ignition and turned for a minute. Took key out, pushed fob button and everything seemed normal again. Idled the car for a minute or two, then went for a 10 mile drive.
Not sure if this fixes it permanently, but that’s the status. I’ll see it works tomorrow.
I then removed the car battery and cleaned the terminals with a wire brush. While the battery is almost 9 years old, and I’ll probably buy a new one, it did measure at almost 13 volts when I reinstalled it fresh from a short hookup with the battery tender. Tightened everything up, installed the key into ignition and turned for a minute. Took key out, pushed fob button and everything seemed normal again. Idled the car for a minute or two, then went for a 10 mile drive.
Not sure if this fixes it permanently, but that’s the status. I’ll see it works tomorrow.
#23
I changed the fob battery with a new one (measured it at 1.5 volts, so it was good) and cleaned the contacts. No difference; The car completely ignored the fob.
I then removed the car battery and cleaned the terminals with a wire brush. While the battery is almost 9 years old, and I’ll probably buy a new one, it did measure at almost 13 volts when I reinstalled it fresh from a short hookup with the battery tender. Tightened everything up, installed the key into ignition and turned for a minute. Took key out, pushed fob button and everything seemed normal again. Idled the car for a minute or two, then went for a 10 mile drive.
Not sure if this fixes it permanently, but that’s the status. I’ll see it works tomorrow.
I then removed the car battery and cleaned the terminals with a wire brush. While the battery is almost 9 years old, and I’ll probably buy a new one, it did measure at almost 13 volts when I reinstalled it fresh from a short hookup with the battery tender. Tightened everything up, installed the key into ignition and turned for a minute. Took key out, pushed fob button and everything seemed normal again. Idled the car for a minute or two, then went for a 10 mile drive.
Not sure if this fixes it permanently, but that’s the status. I’ll see it works tomorrow.
If the battery measured at 1.5 volts, it is completely dead. An A21/23 battery for our remotes is 12 vdc.
https://www.google.com/search?q=a21%...obile&ie=UTF-8
#25
Also, using the charger with the battery disconnected may have helped too.
#26
RL Community Team
Rennlist Member
Rennlist Member
#27
Similar problem?
I think I may be having a similar issue. My 1995 C4 had a dead battery this week, after testing and replacing the battery my remotes no longer worked. I read through the forums regarding resetting the fobs, but it seems this isn’t my issue. Symptoms: doors do not lock/unlock using remote, alarm does not sound when locking/unlocking car manually, doors do not lock/unlock using center console switch, door lights come on when in on position but not just by opening the door. I read that the central locking module rarely goes bad, but maybe we fried the fuse when trying to jump the battery?
#28
RL Community Team
Rennlist Member
Rennlist Member
My 1995 C4 had a dead battery this week, after testing and replacing the battery my remotes no longer worked.doors do not lock/unlock using remote, alarm does not sound when locking/unlocking car manually, doors do not lock/unlock using center console switch, door lights come on when in on position but not just by opening the door. I read that the central locking module rarely goes bad, but maybe we fried the fuse.
Also, when connecting a new battery at the moment it is connected a lot of electrical noise can be introduced into the system leaving the various controllers in a corrupted state. I would disconnect the car battery. Let it sit for a while, potentially clearing controller issues, reconnect it and see if it solves your problem.
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DES993 (08-26-2019)
#29
Rennlist Member
Need Help Please:
Hi All,
Having a very difficult time with this issue.
Have read through several threads and honestly don't know how to proceed at this point.
Appreciate any help, particularly in a step-wise approach.
Here's the situation:
Fobs (I have 2) no longer working to lock & unlock doors (they worked perfectly last week).
Door LED lights are blinking in couplets.
Key fobs are new as of 5/2015 and I replaced the key fob batteries today.
Car has been maintained on a CTEK charger and all lights on dash as well as alarm horn are working.
But, car battery is several years old. Perhaps I should replace the car battery with new?
(As a side question: what do you all recommend for a battery and where to purchase?)
I have read that the code to program the immobilizer is the last 4 digits of the immobilizer serial number.
Which number on the immobilizer is the serial number? Is the immobilizer located under the driver's seat?
How else to get the code? Call dealer and give them VIN?
I can't start the car.
Should I simply have it flat-bedded to the dealer and have them fix it?
Thanks
-Dave
Hi All,
Having a very difficult time with this issue.
Have read through several threads and honestly don't know how to proceed at this point.
Appreciate any help, particularly in a step-wise approach.
Here's the situation:
Fobs (I have 2) no longer working to lock & unlock doors (they worked perfectly last week).
Door LED lights are blinking in couplets.
Key fobs are new as of 5/2015 and I replaced the key fob batteries today.
Car has been maintained on a CTEK charger and all lights on dash as well as alarm horn are working.
But, car battery is several years old. Perhaps I should replace the car battery with new?
(As a side question: what do you all recommend for a battery and where to purchase?)
I have read that the code to program the immobilizer is the last 4 digits of the immobilizer serial number.
Which number on the immobilizer is the serial number? Is the immobilizer located under the driver's seat?
How else to get the code? Call dealer and give them VIN?
I can't start the car.
Should I simply have it flat-bedded to the dealer and have them fix it?
Thanks
-Dave
#30
Burning Brakes
^^^ I’m convinced all my troubles were due to a weak car battery, which I ended up changing and everything’s fine. If your battery is getting old, get a new one before going crazy with the other stuff.