Ignition Circuit - Derbi boulevard 125 4t Workshop Manual

Electrical system
If it does not work, replace the aerial.
If no faults are found, replace the control unit.
CAUTION
BEFORE PROGRAMMING THE NEW ELECTRONIC CONTROL UNIT CHECK THAT NO FAILURE
CODE IS INDICATED. THIS IS TO AVOID SPOILING A NEW CONTROL UNIT UNNECESSARILY.
Specific tooling
020331Y Digital multimeter
Electric characteristic
Resistance value
~ 7 ÷ 9 Ohm
Diagnostic code - 3 flashes
If the 3-flash code is detected, check if the failure occurs when the MASTER key in inserted into the
key switch.
- If the failure disappears when the MASTER key is used, proceed with coding a new service key (Blue).
- If the failure persists, it means that the MASTER key and the control unit are not linked; in this case,
replace the control unit and then encode the keys.
The immobilizer system is efficient when, after switching over to «ON», only a 0.7-sec flash is detected
(see diagram).
In this case, the engine can be started.
Example with programmed control unit, trans-
ponder, programmed key and working aerial. The
ignition is enabled (regular use conditions)

Ignition circuit

All the control operations of the system that entail disconnecting cables (to check connections and the
devices making up the ignition circuit) must be done with the engine off: if this is not done, the controls
might be irretrievably damaged.
The battery provides the basic power supply. The system is adjusted so that the start-up system im-
mediately detects an eventual battery voltage drop, and this is practically irrelevant for the ignition
system.
The Pick-Up is connected to the control unit by a single cable; therefore, the control unit is connected
to the Pick-Up by the chassis and the engine ground lead.
ELE SYS - 70