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Speed Control: Overview Ford Fusion I рестайлинг

Cruise Control Systems 8 illustrations ~3088 words

The speed control system consists of the following components

  1. Speed control switches
  2. Speed control deactivator switch (part of the stoplamp switch)
  3. Stoplamp switch
  4. Clutch pedal speed control deactivator switch (manual transaxle)
  5. Speed control indicator
  6. PCM

Special Tools Illustration Tool Name Tool Number 73III Automotive Meter 105-R0057 or equivalent Vehicle Communication Module (VCM) and Integrated Diagnostic System (IDS) software with appropriate hardware, or equivalent scan tool Restraint System Diagnostic Tool (2 required) 418-F395 Flex Probe Kit 105-R025C or equivalent

Scheme 1

Scheme 1: Speed Control
Scheme 1: Speed Control

Scheme 2

Scheme 2
Scheme 2

Scheme 3

Scheme 3
Scheme 3

Principles of Operation

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

The speed control system is controlled by the PCM. The speed control system is designed to maintain a selected vehicle speed above 48 km/h (30 mph) to the maximum limited vehicle speed. The speed control system is controlled by the steering wheel mounted switches (ON, OFF, SET+, SET- and RESUME), the stoplamp switch, the clutch pedal speed control deactivator switch (manual transaxle), and the speed control deactivator switch (part of the stoplamp switch). The steering wheel mounted switches are hardwired to the PCM through the clockspring.

The speed control functions include

  1. Turning the speed control system on
  2. Setting and maintaining the desired vehicle speed
  3. Accelerating the vehicle speed
  4. Decelerating the vehicle speed
  5. Turning the vehicle speed control system off
  6. Canceling the speed control

Pressing and releasing the ON switch turns the speed control system on. Pressing and releasing the SET+ or SET- switch while the vehicle is traveling at the desired speed activates the speed control system.

Tapping the SET+ or the SET- switch while in the set mode respectively, increases or decreases the maintained vehicle speed by 1.6 km/h (1 mph) per tap. If the respective button is pressed and held, the vehicle speed continues to accelerate or decelerate until the button is released.

Pressing and releasing the OFF switch, or switching the ignition switch to the OFF position, turns the speed control system off. Applying the brake pedal puts the speed control system into the STANDBY mode. Pressing the RESUME button, when the speed control system is in the STANDBY mode causes the vehicle to accelerate to the last set speed. Resume does not function if the OFF button is pressed, the ignition switch is in the OFF position, or if the current vehicle speed is below the minimum operational speed.

The clockspring provides the electrical interface between the steering column wiring and the speed control switches in the steering wheel.

The clutch pedal speed control deactivator switch is incorporated on vehicles equipped with a manual transaxle. When the clutch pedal is applied with the vehicle speed control system engaged, the normally closed switch opens and signals the PCM to deactivate the speed control.

The speed control deactivator switch (part of the stoplamp switch) is provided as an additional safety feature. When the brake pedal is applied, the speed control deactivator switch opens and removes the voltage signal from the PCM input circuit, deactivating the speed control system.

Whenever the speed control system is engaged and active, a speed control icon on the instrument cluster (IC) is illuminated.

The inputs to the PCM are

  1. Output shaft speed (OSS) sensor
  2. Digital transmission range (TR) sensor (automatic transaxle)
  3. Speed control switch
  4. Clutch pedal speed control deactivator switch (manual transaxle)
  5. Speed control deactivator switch (part of the stoplamp switch)
  6. Accelerator pedal position sensor
  7. Smart junction box (SJB)
  8. Parking brake

The outputs of the PCM are

  1. Speed control indicator lamp
  2. Throttle command

The speed control system throttle position is completely controlled by the PCM through the electronically controlled throttle body. Speed control electronics are contained entirely within the PCM.

When the speed control system is active, the PCM corrects for deviations in the actual vehicle speed by proportionally moving the throttle plate. The PCM modulates the throttle to minimize error between the actual vehicle speed and the desired speed.

The PCM strategy uses the throttle control for smooth accelerations.

The PCM sends a message over the controller area network (CAN) to the IC whenever the speed control telltale should be turned on or off.

In the event of an off command or a deactivation request from any source, the speed control system carries out a deactivation and immediately returns the throttle to the idle position.

The speed control system provides self-diagnostics. Speed control is disabled anytime an error is detected in the system. No cluster telltale or message center messages are displayed when faults occur. Fault codes are logged by the PCM.

An electronically controlled throttle system fault also causes the speed control system to be disabled and the malfunction indicator lamp (MIL) illuminates, or a message center message is displayed.

Additionally, the following conditions cause the speed control system to deactivate

  1. Transmission gear selector in a position other than D or OD (automatic transaxle)
  2. Vehicle clutch pedal is applied (manual transaxle)
  3. Speed control set speed is over-ridden with the accelerator pedal for a period longer than 5 minutes
  4. Vehicle speed loss from set speed of greater than 16 km/h (10 mph) occurs
  5. Vehicle speed falls below the minimum allowable limit of 48 km/h (30 mph)
  6. Parking brake is applied
  7. Speed control switch is pressed or stuck for longer than 2 minutes

Normal Operation

The PCM sends a signal through circuit VES10 (WH) to the speed control switches, which passes through the clockspring. The return signal is sent to the PCM through circuit RES08 (GN/BN) and the clockspring. When the brake pedal is applied, the smart junction box (SJB) sends a message to the PCM to deactivate the speed control if engaged.

The speed control deactivator switch (part of the stoplamp switch) interrupts circuit CES09 (VT/OG) removing the voltage signal to the PCM when the brake pedal is applied. This is a redundant signal to the PCM.

This pinpoint test is intended to diagnose the following

  1. PCM not configured for speed control
  2. Stoplamp switch
  3. Clutch pedal position (CPP) switch
  4. Speed control switch
  5. Digital transmission range (TR) sensor
  6. Vehicle speed signal
  7. PCM
CAUTIONUse the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Scheme 4

Scheme 4
Scheme 4
  1. A1 VERIFY PCM CONFIGURATION Enter the following diagnostic mode on the diagnostic tool: Programmable Parameters Verify that the speed control is enabled in the PCM. Is the speed control enabled? YES : Go to A2 . NO : Enable the speed control in the PCM using the scan tool programmable parameters menu. If no parameter exists, REFER to «MODULE CONFIGURATION»(ref-291882) article to carry out PCM programmable module installation (PMI). TEST the system for normal operation.
  2. A2 CHECK FOR DTCs Review the recorded DTCs from the PCM self-test. Are any non-speed control DTCs recorded? YES : REFER to the «Introduction - Gasoline Engines»(ref-291242) article. REPAIR all PCM DTCs and RETEST the speed control. NO : Go to A3 .
  3. A3 CHECK THE SPEED CONTROL COMMAND SWITCH (SCCS) PID Start the engine. Enter the following diagnostic mode on the diagnostic tool: PCM DataLogger With the engine running, monitor the PCM SCCS PID while pressing the speed control switches as follows: Speed Control Switch PID Minimum Value PID Maximum Value OFF 0.00 volts 1.089 volts SET - 2.192 volts 3.057 volts SET + 3.057 volts 3.721 volts RESUME 3.721 volts 4.209 volts ON 4.209 volts 4.556 volts No switch pressed 4.556 volts 4.839 volts Are the PCM SCCS PID values OK? YES : TURN the engine off. Go to A5 . NO : TURN the engine off. Go to A4 .
  4. A4 CHECK THE SPEED CONTROL SWITCH Key in OFF position. Disconnect: PCM C175b Measure the resistance between the PCM C175b-56, circuit VES10 (WH), harness side and the PCM C175b-57, circuit RES08 (GN/BN), harness side while pressing the speed control switches as follows: Speed Control Switch Resistance Value OFF Less than 5 ohms SET - 298 - 304 ohms SET + 596 - 608 ohms RESUME 1,101 - 1,123 ohms ON 2,091 - 2,133 ohms No switch pressed 4,279 - 4,363 ohms Are the speed control switch resistance values OK? YES : Go to A9 . NO : INSTALL a new speed control switch. REFER to «Speed Control Switch»(ref-291942-S22234197662008073000000) . TEST the system for normal operation.
  5. A5 CHECK THE STOPLAMP SWITCH (BOO) PID Key in ON position. Enter the following diagnostic mode on the diagnostic tool: PCM DataLogger Monitor the PCM BOO PID. Apply and release the brake pedal. Does the PID value agree with the brake pedal position? YES : If equipped with an automatic transmission, go to A7 . If equipped with a manual transmission, go to A6 . NO : Go to «Pinpoint Test B»(ref-291942-S38683999182008073000000) .
  6. A6 CHECK THE CPP SWITCH (CPP_TT) PID Enter the following diagnostic mode on the diagnostic tool: PCM DataLogger Monitor the PCM CPP_TT PID while pressing and releasing the clutch pedal. Does the PID value agree with the clutch pedal position? YES : Go to A8 . NO : Go to «Pinpoint Test D»(ref-291942-S34044158672008073000000) .
  7. A7 CHECK THE DIGITAL TR SENSOR (TR) PID Connect: PCM C175b Apply the parking brake. Key in ON position. Enter the following diagnostic mode on the diagnostic tool: PCM DataLogger Monitor the PCM TR PID. Select DRIVE. Does the PID value agree with the transmission range selector lever position? YES : Go to A8 . NO : REFER to «AUTOMATIC TRANSAXLE/TRANSMISSION - AISIN AW21»(ref-291884) article to diagnose the digital TR sensor.
  8. A8 CHECK THE VEHICLE SPEED NOTE: This step may require an assistant. Enter the following diagnostic mode on the diagnostic tool: ABS DataLogger Monitor and record the ABS LF_WSPD (left front wheel speed) PID while driving the vehicle at 48 km/h (30 mph) as indicated on the speedometer. Enter the following diagnostic mode on the diagnostic tool: PCM DataLogger Monitor and record the PCM VSS (vehicle speed signal) PID while driving the vehicle at 48 km/h (30 mph). Does the speed indicated by the ABS LF_WSPD PID match the PCM VSS PID? YES : Go to A9 . NO : REFER to the «Introduction - Gasoline Engines»(ref-291242) article to diagnose the output shaft speed (OSS) sensor signal.
  9. A9 CHECK FOR CORRECT PCM OPERATION Disconnect all the PCM connectors. Check for: corrosion damaged pins pushed-out pins Connect all the PCM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new PCM. REFER to «ELECTRONIC ENGINE CONTROLS - 2.3L»(ref-291907) article or «ELECTRONIC ENGINE CONTROLS - 3.0L (4V)»(ref-291913) article. TEST the system for normal operation. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

When the brake pedal is applied, the smart junction box (SJB) sends a message to the PCM to deactivate the speed control if engaged.

The speed control deactivator switch (part of the stoplamp switch) interrupts circuit CES09 (VT/OG) removing the voltage signal to the PCM when the brake pedal is applied. This is a redundant signal to the PCM.

DTC P1572 sets when the PCM does not sense the proper sequence of the brake pedal input signal from both the speed control deactivator and stoplamp switches when the brake pedal is pressed and released.

DTC P1703 sets when there is an open or short in the deactivator switch circuits or when there is an open or short in the stoplamp circuits.

This pinpoint test is intended to diagnose the following

  1. Fuse
  2. Wiring, terminals or connectors
  3. Speed control deactivator switch (integral to the stoplamp switch)
  4. ABS module
  5. PCM

The PCM sends a signal through circuit VES10 (WH) to the speed control switches, which passes through the clockspring. The return signal is sent to the PCM through circuit RES08 (GN/BN) and the clockspring.

DTC P0579 may set when a speed control switch is stuck or the switch circuits are open, shorted to voltage or shorted to ground.

DTC P0581 sets when the speed control switch circuits are shorted to voltage or open.

This pinpoint test is intended to diagnose the following

  1. Wiring, terminals or connectors
  2. Clockspring
  3. Speed control switch
  4. PCM
CAUTIONUse the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Scheme 5

Scheme 5
Scheme 5

Scheme 6

Scheme 6
Scheme 6

Scheme 7

Scheme 7
Scheme 7

Scheme 8

Scheme 8
Scheme 8
  1. C1 CHECK THE SPEED CONTROL SWITCH CIRCUITRY FOR A SHORT TO VOLTAGE Key in OFF position. Disconnect: PCM C175b Key in ON position. Turn the parking lamps on. Measure the voltage between the PCM C175b-56, circuit VES10 (WH), harness side and ground; and between the PCM C175b-57, circuit RES08 (GN/BN), harness side and ground. Is any voltage present? YES : TURN the parking lamps off. Go to C2 . NO : TURN the parking lamps off. Go to C4 .
  2. C2 CHECK CIRCUITS VES10 (WH) AND RES08 (GN/BN) FOR A SHORT TO VOLTAGE Key in OFF position. Disconnect: Clockspring C218a Key in ON position. Turn the parking lamps on. Measure the voltage between the PCM C175b-56, circuit VES10 (WH), harness side and ground; and between the PCM C175b-57, circuit RES08 (GN/BN), harness side and ground. Is any voltage present? YES : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test. NO : TURN the parking lamps off. Go to C3 .
  3. C3 CHECK THE CLOCKSPRING FOR A SHORT TO VOLTAGE Key in OFF position. Connect: Clockspring C218a WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any air bag module when the battery is connected. Failure to follow these instructions may result in serious personal injury in the event of an accidental deployment. Remove the driver air bag module. Refer to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. Disconnect: Upper Clockspring C218b Connect the restraint system diagnostic tools (418-F395) to the upper clockspring air bag connector. Connect the battery. Key in ON position. Turn the parking lamps on. Measure the voltage between the PCM C175b-56, circuit VES10 (WH), harness side and ground; and between the PCM C175b-57, circuit RES08 (GN/BN), harness side and ground. Is any voltage present? YES : INSTALL a new clockspring. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. DISCONNECT the battery. INSTALL the driver air bag module. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. CLEAR the DTCs. REPEAT the self-test. NO : INSTALL a new speed control switch. REFER to «Speed Control Switch»(ref-291942-S22234197662008073000000) . DISCONNECT the battery. INSTALL the driver air bag module. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. CLEAR the DTCs. REPEAT the self-test.
  4. C4 CHECK THE SPEED CONTROL SWITCH CIRCUITRY FOR A SHORT TO GROUND Key in OFF position. Measure the resistance between the PCM C175b-56, circuit VES10 (WH), harness side and ground; and between the PCM C175b-57, circuit RES08 (GN/BN), harness side and ground. Are the resistances greater than 10,000 ohms? YES : Go to C7 . NO : Go to C5 .
  5. C5 CHECK THE CLOCKSPRING FOR A SHORT TO GROUND Remove the driver air bag module. Refer to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. Disconnect: Upper Clockspring C218b Measure the resistance between the PCM C175b-56, circuit VES10 (WH), harness side and ground; and between the PCM C175b-57, circuit RES08 (GN/BN), harness side and ground. Are the resistances greater than 10,000 ohms? YES : INSTALL a new speed control switch. REFER to «Speed Control Switch»(ref-291942-S22234197662008073000000) . INSTALL the driver air bag module. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. CLEAR the DTCs. REPEAT the self-test. NO : Go to C6 .
  6. C6 CHECK CIRCUITS VES10 (WH) AND RES08 (GN/BN) FOR A SHORT TO GROUND Disconnect: Clockspring C218a Measure the resistance between the PCM C175b-56, circuit VES10 (WH), harness side and ground; and between the PCM C175b-57, circuit RES08 (GN/BN), harness side and ground. Are the resistances greater than 10,000 ohms? YES : INSTALL a new clockspring. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. INSTALL the driver air bag module. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. CLEAR the DTCs. REPEAT the self-test. NO : REPAIR the circuit in question. INSTALL the driver air bag module. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. CLEAR the DTCs. REPEAT the self-test.
  7. C7 CHECK THE SPEED CONTROL SWITCH CIRCUITRY FOR AN OPEN Measure the resistance between the PCM C175b-56, circuit VES10 (WH), harness side and the PCM C175b-57, circuit RES08 (GN/BN), harness side. Is the resistance between 4,279 and 4,363 ohms? YES : Go to C10 . NO : Go to C8 .
  8. C8 CHECK CIRCUITS VES10 (GN/BK) AND RES08 (GN/BN) FOR AN OPEN Disconnect: Clockspring C218a Measure the resistance between the PCM C175b-56, circuit VES10 (WH), harness side and the clockspring C218a-15, circuit VES10 (WH), harness side; and between the PCM C175b-57, RES08 (GN/BN), harness side and the clockspring C218a-14, circuit RES08 (GN/BN), harness side. Are the resistances less than 5 ohms? YES : Go to C9 . NO : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
  9. C9 CHECK THE CLOCKSPRING Remove the driver air bag module. Refer to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. Measure the resistance between the clockspring C218a pin 15, component side and the upper clockspring C218b pin 8, component side; and between the clockspring C218a pin 14, component side and the upper clockspring C218b pin 9, component side. Are the resistances less than 5 ohms? YES : INSTALL a new speed control switch. REFER to «Speed Control Switch»(ref-291942-S22234197662008073000000) . INSTALL the driver air bag module. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. CLEAR the DTCs. REPEAT the self-test. NO : INSTALL a new clockspring. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. INSTALL the driver air bag module. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. CLEAR the DTCs. REPEAT the self-test.
  10. C10 CHECK FOR CORRECT PCM OPERATION Disconnect all the PCM connectors. Check for: corrosion damaged pins pushed-out pins Connect all the PCM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new PCM. REFER to «ELECTRONIC ENGINE CONTROLS - 2.3L»(ref-291907) article or «ELECTRONIC ENGINE CONTROLS - 3.0L (4V)»(ref-291913) article. INSTALL the driver air bag module. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. TEST the system for normal operation. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. INSTALL the driver air bag module. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-291881) article. CLEAR the DTCs. REPEAT the self-test.

Vehicles equipped with a manual transaxle have an additional clutch pedal speed control deactivator switch. The PCM sends a signal through circuit CE904 (GN/VT) to the clutch pedal speed control deactivator switch. The return signal is sent to the PCM through circuit RE407 (YE/VT).

DTC P0833 sets when there is an open in the clutch pedal speed control deactivator switch circuits.

This pinpoint test is intended to diagnose the following

  1. Wiring, terminals or connectors
  2. Clutch pedal speed control deactivator switch
  3. PCM

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