Before Battery Change
- When was/or when did you notice alarm green light illuminated?
- When after alarm was disarmed, did green light shine?
First thing to check would be electrical connections starting from the battery.
- Follow positive wire lead from battery to fuse box connections. (Should be along driver side frame rail, or near battery.)
- Follow wrie harness to Relay Center. (Find Alarm Relay/Fuse)
- Also to Power Distribution Center. (upper driver corner engine bay)
Relay Switch and Fuse to Alarm should be okay, given the alarm green light illumination.
The Cars Brain, ECM Engine Control Module, manages messeges between power BattV and Alarm, also other modules and various sensors throughout the vehicle.
When Battery Supply was disconnected, something happened, that stunned the memory in the ECM.
Yes, the alarm does need resetting, its actually the memory messages saved in ECM need to be Refreshed.
(saying "alarm needs resetting") sounds like alarm is broken, when that is not the case. Similar scenario is, when smart phone screen webpage freezes(alarm memory info in ECU). No buttons work, not even power button (Key Fob control). Only way to gain access is to remove battery.
Lets try an experiment, this will be to loose still/saved frozen information, stuck in computer memory.
How to Reset Vehicle Computer.
- Remove Neggative Post connection.
- Remove Positive Post connection.
- Let vehicle sit over Two Minutes, this time allows capacitors in vehicle Modules (ECM/PCM, TCM), to release any/all stored voltage, also any voltage in Vehicles ground circuit will be released.
- (I would typically wait 15 minutes) Capacitors with out constant Voltage input, will disipate rather quickly, depending on capacity size.
- With Battery Still Disconnected. Open Driver Car door, and turn Ignition to RUN Position.
- Reconnect Positive Post.
- Reconnect Negative Post.
- IGNITION is in RUN Position, when reconnecting Battery. Driver Door Is Open.
7. Turn Ignition to Off.
8. Hit LOCK Button On Driver Door Switch to Reinitialize Alarm.
- Notice if alarm green light is illuminated.
- Be SURE Key Fob not locked in car.