Steering Column Switches: Overview Ford Focus II рестайлинг

The steering column switches consist of the following

1. Multifunction switch
2. Ignition switch

The steering column switches receive driver inputs and send signals to various components. The multifunction switch controls the windshield wipers, hazard flasher, turn signal, headlamp low/high beam and headlamp dimmer/flash-to-pass. The ignition switch is used in conjunction with the lock cylinder key to start the vehicle. When the lock cylinder key is switched to different positions, it moves linkages which enable the ignition switch to send battery voltage to various components.

Special Tools Illustration Tool Name Tool Number 73III Automotive Meter 105-R0057 or equivalent Flex Probe Kit 105-R025B or equivalent Vehicle Communication Module (VCM) and Integrated Diagnostic System (IDS) software with appropriate hardware, or equivalent scan tool

Scheme 1

Scheme 2

Principles of Operation

Note. The smart junction box (SJB) is also identified as the generic electronic module (GEM).

Ignition Switch - The ignition switch is controlled by the ignition lock cylinder with a key. When the ignition cylinder is turned using the key, a mechanical connection positions the ignition switch to the selected position and allows the ignition switch to send voltage to specific components. The ignition switch is contained in the steering column lock module, if a new ignition switch needs to be installed, then a new lock module must be installed.

Multi-function Switch - The multi-function switch (flash-to-pass, high beam, turn signal and windshield wiper/washer) controls the various components electrically. The multi-function switch is hard-wired to the SJB and controls a ground signal for the high beam, flash-to-pass and turn signal functions. The multi-function switch is also hard-wired to the smart wiper module and controls a ground signal for the various wiper and washer functions.

For headlamp and turn signal concerns, refer to EXTERIOR LIGHTING article. For wiper and washer concerns, refer to WIPERS AND WASHERS article.

Normal Operation

The ignition switch receives fused battery voltage along circuit SBP27 (BU/RD) from smart junction box (SJB) fuse 27 (20A). The ignition switch then sends that voltage out to the SJB and the battery junction box (BJB) depending on ignition switch position. The ignition switch has 4 possible states

1. OFF - Power on key-in ignition circuit CDC30 (BU/GY) when the ignition key is inserted into the ignition switch. If the key is not in the ignition switch, then there will be no power on circuit CDC30 (BU/GY).
2. ACC - Power on circuit CDC33 (VT/GN).
3. RUN - Power on circuit CDC32 (BN/YE).
4. START - Power on circuit CDC35 (BU/WH).

This pinpoint test is intended to diagnose the following

1. Fuse
2. Wiring, terminals or connectors
3. Ignition switch
4. SJB

When the ignition switch is placed in the ACC position, fused ignition voltage is sent to the smart junction box (SJB) along circuit CDC33 (VT/GN).

This pinpoint test is intended to diagnose the following

1. Fuse(s)
2. Wiring, terminals or connectors
3. Ignition switch

When the ignition switch is placed in the RUN position, fused ignition voltage is sent to the smart junction box (SJB) along circuit CDC32 (BN/YE).

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. Ignition switch
3. SJB

When the ignition switch is placed in the START position, fused ignition voltage is sent to the battery junction box (BJB) along circuit CDC35 (BU/WH).

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. Ignition switch

When the ignition switch is placed in the START position, fused ignition voltage is sent to the start diode in the battery junction box (BJB) along circuit CDC35 (BU/WH) and then to the smart junction box (SJB) and the PCM along circuit CE619 (BU/BN). The ignition switch is spring loaded to automatically return to the RUN position after being placed in the START position.

1. B2A20 Ignition Stuck in START - The SJB continuously monitors the ignition switch state, if the SJB receives a START signal for more than 30 seconds, DTC B2A20 will be set.

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. Ignition switch
3. SJB
4. BJB
5. PCM

The ignition switch receives fused battery voltage along circuit SBP27 (BU/RD) from smart junction box (SJB) fuse 27 (20A). The ignition switch then sends that voltage out to the SJB and the battery junction box (BJB) depending on ignition switch position. The SJB monitors circuit CDC32 (BN/YE) (run/start) and circuit CDC33 (VT/GN) (run/accessory) at all times.

1. DTC U2472 Unexpected Ignition State - DTC U2472 will only set during the on-demand self test if the SJB cannot detect the RUN signal or cannot detect the ignition switch state at all during the self-test.

This pinpoint test is intended to diagnose the following

1. Wiring, terminals or connectors
2. Ignition switch
3. SJB

See also:
• COMPONENT TESTING