This just happened to me today- connect the battery, put your key in the drivers side door, lock then unlock. That's it.
New battery fixed the problem.
I would take it to either the dealer or a shucks/autozone asap to have the battery/alternator checked. You could have a open wire, or an alternator problem. Once the battery gets really low you will not be able to turn off the security system and you will have to have it towed to the dealer to have a new battery and the system reprogrammed. You will not be able to jump start the jeep because the security system will not disengage if the battery is dead FYI, I tried that it didnt work.
There never was a 1974 Jeep Grand Cherokee.
By disconnecting the battery.
If the security system on a 1991 Jeep Cherokee will not allow the jeep to start and the key will not turn in the lock, disconnect the battery for a few minutes. Try the key in the lock with the battery disconnected. If it works the first time, reconnect the battery and the system should be reset. If the key does not work in the lock, reconnect the battery and reprogram the key fob.
Note penciled into friend's 95 GC owner manual sez "pull fuses 6 & 7 (security system) to stop battery drain". Don't know if it works.
Disconnect the battery
Your battery is toast, or check the pin switch under the hood.10.00 part. to reset the sec syst. lock/unlock passdoor
Depends. That system is a real bear. IF you have a battery that is 'suspect' in any way, you need to replace it with a quality battery. the security module will dump into 'security' status when the voltage drops during crank over. A healthy battery is really important on this system. Also, check the door entry key switches AND the tailgate switch which is a magnetic proximity switch as opposed to the front door microswitches that hang on the entry key cylinder tails. Next, check or just disconnect the hood security plunger switch near the battery. The possibility exists that the overhead console is contributing to your problem as it is wired to the security module. I have a 92 Cherokee and have been holding my breath for 5 years that it continues to run. I had an infrared security key built by a firm I found online. The jeep came without one. as the front door lock switches had failed and I got tired of unlocking the system at the tailgate, I wanted a normal way to unlock the doors and disarm the security system. Good luck on your problem.
Low battery or power surge
H
The only method of disarming the security system is thru the door locks, if it does not disarm; this will entail a fault in the security system. First, the vehicle battery will have to be tested, a low, or shorted battery can trigger the security as well. If the battery is good, the sytem will need electrical diagnosis, which I recommend be done at the dealer, since they are more familiar with this vehicle's security system, than most independent facilities are.