Joey
03-29-2011, 10:45 AM
The following info has been gathered from other sites or posts, this is not my info.
The 94 - 96 Discovery and 1994 - 1995 RR Classic share a similar perimetric alarm system that was modified in 1995 and again in 1996. The basic perimetric alarm system provides protection in conjunction with the opening of the hood, tailgate or doors. This security system will be separated into different sections to assist in the explanation of this system.
Components
- ECU - The 1994 RR Classic security ECU is attached to the steering column support, all other security ECUs are located at the right lower dash.
- CENTRAL DOOR LOCKING (CDL)
The security ECU incorporates the CDL function including the CDL inertia switch. If an impact occurs the inertia switch unlocks the doors and turns on the hazard flashers. The flashers can be canceled by turning the ignition switch off for 30 seconds .
- Siren - The vehicle horn is used for the system sounder/siren.
- Relays - Three relays are used in the system; one for lamp flash, one for horn operation and one for interior lamp illumination during system disarming feature.
- Door Locks - Door locks incorporate switches indicating key lock and sill button operation.
- Antenna - The antenna is located in the "A" post and is routed to the instrument cluster. *
- Remotes - Two hand held remotes are supplied with each vehicle.
System Function
- Arming - The system can be armed (and the doors/tailgate locked) via the remote or by the key. To indicate
* 1994 Classic antenna located in front of instrument cluster
successful arming, the following occurs: hazard lamps flash three times, fascia mounted LED flashes rapidly for 10 seconds , then continues to flash at a slower rate (1 flash/second) .
- Disarming - The system can be disarmed via the remote or door locks. On system disarm, the hazards flash once and the fascia mounted LED stops flashing. A relay will trip the interior lamp delay (ILD) unit causing the interior lamps to illuminate.
- System Override - If the door key is held in the locked position for a period of 5 - 8 seconds the vehicle will lock but the security system will not arm.
- Mislock - If any of the doors or the hood is left open once the alarm system is armed, the hazard warning lights will fail to flash, and the anti-theft indicator light will not illuminate until 10 seconds have elapsed. This indicates 'mislock' condition. If an open door or hood is subsequently closed, the doors will unlock (after a 5 second delay) and immediately lock again. The alarm is then armed as normal. Dead battery results in one long flash...No flash mean the ECU is seeing a door open.
- Automatic Re-Locking - If the system detects a mislock condition (i.e. (,ne door unlocked) on system arming, a short delay will occur about 5 seconds then a CDL unlock signal will be issued by the security ECU followed by a CDL lock signal which will re-lock all doors and the tailgate. In the example above, if the doors were subsequently closed all doors would unlock, a short delay would occur, then an unlock signal would be sent followed by a lock signal. All doors would then be locked.
- Low Remote Battery Indicator - A counter in the remote, tracks remote activity. (Estimated usage for one year), the hazard lamps will flash once on system arming, indicating remote battery replacement is required. To reset the remote, remove the battery, push the button and replace battery.
- Power-Up Memory - The system always remembers what state it was last in, even if the battery is disconnected. When reconnecting a battery, realize that the system could be armed and could re-lock.
Transmitter Code Learning Must Be Performed if ECU/Remote is Replaced
* The transmitter learning sequence is best carried out by two persons, in the following order. Hood open with one person holding the hood alarm switch pressed down. The hood alarm switch is located next to the windshield washer reservoir.
Access the learn mode by performing the following steps in sequence, a through e, within 8 seconds .
Ignition off, driver's door lock button up,, assistant depressing hood alarm switch.
Turn ignition on, then off.
Depress and raise driver's door lock button.
Assistant release hood alarm switch.
Turn ignition on, then off.
If the learn mode has been correctly programed, the LED will now light, and the horn will sound for 100 milliseconds . If this does not occur, restart at Step 1a. * 94 - 95 Systems - 96 Discovery uses TestBook
Press and hold button on the first remote. The LED on the remote will light and then extinguish after approximately 3 seconds .
The vehicle LED should now flash at 8 cycles per second for a period of one second , then remain on steady. This signifies that the first code has been received correctly and the unit is awaiting another code. If the LED does not perform as above, restart the procedure at Step 1a.
Press and hold the button to the second remote. The LED on the remote will light and then extinguish after approximately 3 seconds .
The vehicle LED should now flash at 8 cycles per second for a period of 1 second , then go off. This signifies that the second code has been received correctly, and the learn sequence has been terminated. If the LED does not perform as above, restart the procedure at Step 1a. NOTE: The sequence can be terminated at any time by turning on the ignition. The ECU is capable of storing two remote transmitter codes and the codes of both remotes must be learned during the same sequence.
Security System Modifications
1995 System Changes Are As Follows :
Starter motor inhibit if the doors, hood or tailgate are open after the system has been armed, the alarm will sound and the electrical circuit between the starter motor and ignition key will be disabled (starter relay).
Interior light feature will illuminate for 15 seconds or until the ignition switch is turned, whenever the alarm system is deactivated using the remote handset.
1996 Discovery Security System Changes Are As Follows :
New ECU - same location.
Antenna wire not coax cable - new location, not in "A" pillar, now in front of instrument cluster.
Different remote handset - 2 button (lock/unlock) instead of one.
Rolling code for security between ECU and remote handset.
NOTE: Code can be lost if battery discharges or is disconnected in vehicle or remote handset or remote pushed too many times beyond remote range.
The 94 - 96 Discovery and 1994 - 1995 RR Classic share a similar perimetric alarm system that was modified in 1995 and again in 1996. The basic perimetric alarm system provides protection in conjunction with the opening of the hood, tailgate or doors. This security system will be separated into different sections to assist in the explanation of this system.
Components
- ECU - The 1994 RR Classic security ECU is attached to the steering column support, all other security ECUs are located at the right lower dash.
- CENTRAL DOOR LOCKING (CDL)
The security ECU incorporates the CDL function including the CDL inertia switch. If an impact occurs the inertia switch unlocks the doors and turns on the hazard flashers. The flashers can be canceled by turning the ignition switch off for 30 seconds .
- Siren - The vehicle horn is used for the system sounder/siren.
- Relays - Three relays are used in the system; one for lamp flash, one for horn operation and one for interior lamp illumination during system disarming feature.
- Door Locks - Door locks incorporate switches indicating key lock and sill button operation.
- Antenna - The antenna is located in the "A" post and is routed to the instrument cluster. *
- Remotes - Two hand held remotes are supplied with each vehicle.
System Function
- Arming - The system can be armed (and the doors/tailgate locked) via the remote or by the key. To indicate
* 1994 Classic antenna located in front of instrument cluster
successful arming, the following occurs: hazard lamps flash three times, fascia mounted LED flashes rapidly for 10 seconds , then continues to flash at a slower rate (1 flash/second) .
- Disarming - The system can be disarmed via the remote or door locks. On system disarm, the hazards flash once and the fascia mounted LED stops flashing. A relay will trip the interior lamp delay (ILD) unit causing the interior lamps to illuminate.
- System Override - If the door key is held in the locked position for a period of 5 - 8 seconds the vehicle will lock but the security system will not arm.
- Mislock - If any of the doors or the hood is left open once the alarm system is armed, the hazard warning lights will fail to flash, and the anti-theft indicator light will not illuminate until 10 seconds have elapsed. This indicates 'mislock' condition. If an open door or hood is subsequently closed, the doors will unlock (after a 5 second delay) and immediately lock again. The alarm is then armed as normal. Dead battery results in one long flash...No flash mean the ECU is seeing a door open.
- Automatic Re-Locking - If the system detects a mislock condition (i.e. (,ne door unlocked) on system arming, a short delay will occur about 5 seconds then a CDL unlock signal will be issued by the security ECU followed by a CDL lock signal which will re-lock all doors and the tailgate. In the example above, if the doors were subsequently closed all doors would unlock, a short delay would occur, then an unlock signal would be sent followed by a lock signal. All doors would then be locked.
- Low Remote Battery Indicator - A counter in the remote, tracks remote activity. (Estimated usage for one year), the hazard lamps will flash once on system arming, indicating remote battery replacement is required. To reset the remote, remove the battery, push the button and replace battery.
- Power-Up Memory - The system always remembers what state it was last in, even if the battery is disconnected. When reconnecting a battery, realize that the system could be armed and could re-lock.
Transmitter Code Learning Must Be Performed if ECU/Remote is Replaced
* The transmitter learning sequence is best carried out by two persons, in the following order. Hood open with one person holding the hood alarm switch pressed down. The hood alarm switch is located next to the windshield washer reservoir.
Access the learn mode by performing the following steps in sequence, a through e, within 8 seconds .
Ignition off, driver's door lock button up,, assistant depressing hood alarm switch.
Turn ignition on, then off.
Depress and raise driver's door lock button.
Assistant release hood alarm switch.
Turn ignition on, then off.
If the learn mode has been correctly programed, the LED will now light, and the horn will sound for 100 milliseconds . If this does not occur, restart at Step 1a. * 94 - 95 Systems - 96 Discovery uses TestBook
Press and hold button on the first remote. The LED on the remote will light and then extinguish after approximately 3 seconds .
The vehicle LED should now flash at 8 cycles per second for a period of one second , then remain on steady. This signifies that the first code has been received correctly and the unit is awaiting another code. If the LED does not perform as above, restart the procedure at Step 1a.
Press and hold the button to the second remote. The LED on the remote will light and then extinguish after approximately 3 seconds .
The vehicle LED should now flash at 8 cycles per second for a period of 1 second , then go off. This signifies that the second code has been received correctly, and the learn sequence has been terminated. If the LED does not perform as above, restart the procedure at Step 1a. NOTE: The sequence can be terminated at any time by turning on the ignition. The ECU is capable of storing two remote transmitter codes and the codes of both remotes must be learned during the same sequence.
Security System Modifications
1995 System Changes Are As Follows :
Starter motor inhibit if the doors, hood or tailgate are open after the system has been armed, the alarm will sound and the electrical circuit between the starter motor and ignition key will be disabled (starter relay).
Interior light feature will illuminate for 15 seconds or until the ignition switch is turned, whenever the alarm system is deactivated using the remote handset.
1996 Discovery Security System Changes Are As Follows :
New ECU - same location.
Antenna wire not coax cable - new location, not in "A" pillar, now in front of instrument cluster.
Different remote handset - 2 button (lock/unlock) instead of one.
Rolling code for security between ECU and remote handset.
NOTE: Code can be lost if battery discharges or is disconnected in vehicle or remote handset or remote pushed too many times beyond remote range.