Indicator Led/Status Panel Faulty

Basic Alarm And Guard Alarm II:
LED must not be supplied with 12 V by bridging at relay center etc.

Sources of fault
Open-circuit in LED/status panel ground lead.
Open-circuit in LED/status panel signal lead/s.
Short-circuit to ground in LED/status panel signal lead/s.
Short-circuit to battery voltage in LED/ status panel signal lead/s.
Fault in LED/status panel.
Fault in alarm control module.







LA. Basic Alarm And Guard Alarm II
Indicator LED indicating wrongly or not at all.
Fault-tracing starts with LA1.

Guard Alarm II Fitted As Accessory:
In cars without ECC, the indicator LED is located on the driver's side speaker frame. The leads to the LED run from the top of the control module by a 5-pin connector. Undo LED 2-pin connector before testing as below. This can be accessed from the relay center. The control module must also be in place. Otherwise, fault-tracing for Guard Alarm II is as below.

LA1 Check Ground Lead

Deactivate alarm.




Ignition off.




Insert a screwdriver by the side of the indicator LED and pry it carefully up.
Undo indicator LED connector.
In cars without ECC, the connector is 2-pin, while in cars with ECC it is 5-pin, as the air-conditioning sun sensor is integrated in the indicator LED.





Connect an ohmmeter between LED connector position 2 and ground.




Cars with ECC:
Connect an ohmmeter between LED connector position 5 (ground) and ground. Ohmmeter should read approx. 0 ohm.

If reading is OK:
Check signal lead resistance to ground LA2.

If reading is incorrect:
Check LED ground lead for open-circuit as per WA3. Deal with fault or replace lead. SEE Other Fault-Tracing Test.



LA2 Check Signal Lead Resistance To Ground

Ignition off.




Connect an ohmmeter to LED connector between position 1 and position 2 (ground).





Cars with ECC:
Connect an ohmmeter to LED connector between position 1 and position 5 (ground). Ohmmeter should read very high resistance.

If reading is OK:
Check signal lead supply LA3.

If reading is incorrect:
Check LED signal lead for short-circuit to ground as per WA4 SEE Other Fault-Tracing Test. Deal with fault or replace lead.



LA3 Check Signal Lead Supply
Ignition on.





Ignition off





Connect a voltmeter to LED connector between position 1 and position 2 (ground).





Cars With ECC:
Connect a voltmeter to LED connector between position 1 and position 5 (ground). Voltmeter should read 0 V.

If reading is OK:
Check signal lead resistance LA4.

If reading is incorrect:
Check LED signal lead for short-circuit to supply as per WA5 SEE Other Fault-Tracing Test. Deal with fault or replace lead.


LA4 Check Signal Lead Resistance

Testing Basic Alarm and Guard Alarm II with indicator LED mounted on instrument panel (dashboard):

Ignition off.
Remove alarm control module (position 210/211).





Bridge alarm relay plinth between position DI and position 31 (ground). Connect an ohmmeter to LED connector between position 1 and position 2 (ground). Ohmmeter should read approx. 0 ohm.





Testing Guard Alarm II with indicator LED located on speaker frame:

Ignition off.





Disconnect connector from alarm control module.
Connect an ohmmeter between 2-pin connector position 1 and 5-pin connector position 1. Ohmmeter should read approx. 0 ohm.





If reading is OK:
Check supply LA5.

If reading is incorrect:
Check LED signal lead for open-circuit as per WA3 SEE Other Fault-Tracing Test. Deal with fault or replace lead.



LA5 Check Supply

Ignition off.
Remove bridge from alarm relay plinth between position DI and position 31 (ground). Replace alarm control module (position 210/211).





Activate alarm.





Wait at least 10 seconds.





Trigger alarm (e.g. by opening hood (bonnet).





Deactivate alarm.





Connect a voltmeter to LED connector between position 1 and position 2 (ground).

Cars with ECC:
Connect a voltmeter to LED connector between position 1 and position 5 (ground). Voltmeter should read at least 4 V.





If reading is OK:
Try another LED.

If reading is incorrect:
Try another alarm control module by Guard Alarm I or II (only) Test of Fault-Tracing in Alarm Wiring Harness.

Guard Alarm II:
Run control module self-test in Guard Alarm II (only) Test before replacing control module.



LB. Guard Alarm I only

Status panel Indicating wrongly or not at all.


NOTE: If status LEDs are giving long single flashes, this means that the key code is not programed in See Description and Operation.


Fault-tracing starts with LB1.

LB1 Check Control Module

Deactivate alarm.





Ignition off.
Disconnect 10-pin connector from control module.





Test A:
Connect an ohmmeter to alarm control module between position K1 (ground) and ground. Ohmmeter should read approx. 0 ohm.





Test B:
Connect a voltmeter to alarm control module between position K4 and K1 (ground). Voltmeter should read battery voltage.





Test C:
Connect a voltmeter to alarm control module between position K2 and K1 (ground). Voltmeter should read between 0 and 5 V.





Test D:
Connect a voltmeter to alarm control module between position k3 and K1 (ground). Voltmeter should read 5 V.




If readings are OK:
Check leads between connector LB2.

If any reading is incorrect:
Try another alarm control module after Fault-Tracing in Alarm Wiring Harness of Guard Alarm I or II (only).

Guard Alarm II:
Run control module self-test in Guard Alarm I or II (only) Test before replacing control module.


LB2 Check Leads Between Connectors





Check that leads between 10-pin and yellow 4-pin connector are connected as below:
Connect an ohmmeter in turn between
position K1 (10-pin) and position 4 (4-pin)
position K2 (10-pin) and position 2 (4-pin)
position k3 (10-pin) and position 1 (4-pin)
position k4 (10-pin) and position 3 (4-pin) on the two connectors.
Ohmmeter should read approx. 0 ohm.





If readings are OK:
Check ground lead LB3.

If any reading is incorrect:
Check lead concerned for open-circuit as per WA3 SEE Other Fualt-Tracing Test. Deal with fault or replace lead.


LB3 Check Ground Lead

Ignition off.
Replace 10-pin connector in alarm control module.
Connect an ohmmeter between the yellow 4-pin connector position 4 (ground) and ground. Ohmmeter should read approx. 0 ohm.





If reading is OK:
Check supply to status panel LB4.

If reading is incorrect:
Check lead between status panel yellow 4-pin connector position 4 and alarm control module 10-pin connector position K1 for open-circuit as per WA3 SEE Other Fault-Tracing Test. Deal with fault or replace lead.


LB4 Check Supply To Status Panel

Ignition off.
Connect a voltmeter to the yellow 4-pin connector between position 3 and position 4 (ground). Voltmeter should read battery voltage.





If reading is OK:
Check signal lead to status panel LB5.

If reading is incorrect:
Check lead between status panel yellow 4-pin connector position 3 and alarm control module 10-pin connector position k4 for short-circuit to ground as per WA4 SEE Other Fault-Tracing Test. Deal with fault or replace lead.

LB5 Check Signal Lead To Status Panel

Ignition off.
Connect a voltmeter to the yellow 4-pin connector between position 1 and position 4 (ground).
Voltmeter should read approx. 5 V.





If reading is OK:
Check signal lead from status panel LB6.

If reading is incorrect:
Check lead between status panel yellow 4-pin connector position 1 and alarm control module 10-pin connector position K3 for short-circuit to ground as per WA4 and short-circuit to supply as per WA5 SEE Other Fault-Tracing Test. Deal with fault or replace lead.



LB6 Check Signal Lead From Status Panel

Ignition off.
Connect a voltmeter to the yellow 4-pin connector between position 2 and position 4 (ground).
Voltmeter should read between 0 and 5 V.





If reading is OK:
Try another status panel.

If reading is incorrect:
Check lead between status panel yellow 4-pin connector position 2 and alarm control module 10-pin connector position K2 for short-circuit to ground as per WA4 and short-circuit to supply as per WA5 SEE Other Fault-Tracing Test. Deal with fault or replace lead.