Clarion S400, Install Manual

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type G: positive (+) multiplex
The door lock switch or door key cylinder may contain either one or two resistors.
Single-Resistor Type
If one resistor is used in the door lock switch/key cylinder, the wire will pulse (+)12V in one direction
and less than (+)12V when operated in the opposite direction.
Two-Resistor Type
If two resistors are used in the factory door lock switch/key cylinder, the switch/key cylinder will read
less than (+)12V in both directions.
Determining the Proper Resistor Values
To determine the resistor values, the door lock switch/key cylinder must be isolated from the factory
door lock system. For testing, use a calibrated digital multimeter that is set to ohms.
1. Cut the output wire from the door lock switch/key cylinder in half.
2. Test with the meter from the switch side of the cut door lock switch/key cylinder wire to a reliable
constant (+)12V source. Some good constant (+)12V references are the power input source to the
door lock switch/key cylinder, the ignition switch power wire, or the (+) terminal of the battery.
3. Operate the door lock switch/key cylinder in both directions to determine the resistor values. If
the multimeter displays zero resistance in one direction, no resistor is needed for that direction.
4. Once the resistor value(s) is determined, refer to the wiring diagram for proper wiring.
IIM MPPO ORRTTA AN NTT!! To ensure an accurate resistance reading, do not touch the resistor or leads
during testing.