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Starting System: Overview Ford Focus I facelift

Starter 12 illustrations ~1875 words

Principles of Operation

On vehicles equipped with automatic transaxles, when the ignition switch is turned to the START position and the vehicle is in the NEUTRAL or PARK position, the starter relay switches power to the starter solenoid causing the starter motor to engage.

Vehicles equipped with manual transaxles have a start inhibit switch in the starter control circuit. When the clutch pedal is applied and the ignition switched is turned to the START position, the starter relay switches power to the starter solenoid causing the starter motor to engage.

The starting system is electronically controlled by the passive anti-theft system (PATS). The PATS recognizes the correct electronically coded ignition key and signals the PCM to provide a ground for the starter relay. The energized relay provides voltage to the starter solenoid, thereby allowing the starter motor to activate.

Normal Operation

Under normal operation, the battery junction box (BJB) supplies constant power to the starter relay on circuit 30-BB9 (RD) through fuse F1.8 (30A). On vehicles with automatic transaxles, when the key is placed in the START position with the vehicle in PARK or NEUTRAL, the transmission range (TR) sensor provides power on circuit 50S-BB12 (GY)/50-BB2 (GY/BK) and the powertrain control module (PCM) provides ground on circuit 31S-BB16 (BK/RD). On vehicles with manual transaxles, when the key is placed in the START position with the clutch pedal depressed, the start inhibit switch provides power on circuit 50-BB12 (GY)/50-BB2 (GY/BK) and the PCM provides ground on circuit 31S-BB16 (BK/RD). The coil of the relay is energized and sends power to the starter motor on circuit 50-BB12 (GY)/50-BB2 (GY/BK).

Possible Causes

  1. Battery
  2. Starter motor
  3. Relay
  4. Circuit

Scheme 2

Scheme 2: PINPOINT TEST A: THE ENGINE DOES NOT CRANK/THE RELAY DOES CLICK
Scheme 2: PINPOINT TEST A: THE ENGINE DOES NOT CRANK/THE RELAY DOES CLICK

Scheme 3

Scheme 3
Scheme 3

Scheme 4

Scheme 4
Scheme 4

Scheme 5

Scheme 5
Scheme 5

Scheme 6

Scheme 6
Scheme 6

Scheme 7

Scheme 7
Scheme 7
  1. A1 CHECK THE BATTERY Check the battery with a Midtronics tester. Carry out the battery capacity test using a scan tool. Is the battery OK? YES : Go to A2 . NO : INSTALL a new battery. REFER to «BATTERY, MOUNTING AND CABLES»(ref-278287) article. CHECK the battery with a Midtronics tester. TEST the system for normal operation.
  2. A2 CHECK THE STARTER RELAY Disconnect: Starter Relay Carry out the ISO mini relay component test. Refer to appropriate COMPONENT TESTING article. Is the relay OK? YES : Go to A3 . NO : INSTALL a new starter relay. TEST the system for normal operation.
  3. A3 CHECK THE VOLTAGE TO THE STARTER RELAY CIRCUIT 30-BB9 (RD) Key in START position. Measure the voltage between central junction box (CJB) starter relay socket C2163-30, circuit 30-BB9 (RD) and ground. Is the voltage greater than 10 volts? YES : Go to A4 . NO : REPAIR circuit 30-BB9 (RD) for an open. TEST the system for normal operation.
  4. A4 CHECK CIRCUIT 50-BB12 (GY)/50-BB2 (GY/BK) FOR AN OPEN Key in OFF position. Disconnect: Starter Motor C197 Automatic transaxle: Place the vehicle in PARK. Measure the resistance between starter motor C197-2, circuit 50-BB12 (GY)/50-BB2 (GY/BK) and CJB starter relay socket C2163-87, circuit 50-BB12 (GY). Is the resistance less than 5 ohms? YES : Go to A5 . NO : For manual transaxle, REPAIR circuit 50-BB12 (GY)/50-BB2 (GY/BK) for an open. TEST the system for normal operation. For automatic transaxle, go to A6 .
  5. A5 CHECK THE STARTER MOTOR FEED Measure the voltage between starter motor C197-1, circuit 30-BB10 (RD) and ground. Is the voltage greater than 10 volts? YES : CLEAN and TIGHTEN all positive battery cable connections. TEST the system for normal operation. If the concern persists, INSTALL a new positive battery cable. NO : REPAIR circuit 30-BB10 (RD) for an open. TEST the system for normal operation.
  6. A6 CHECK CIRCUIT 50-BB12 (GY)/50-BB14 (GY/RD) FOR AN OPEN Disconnect: TR Sensor C167 Measure the resistance between CJB starter relay socket C2163-87, circuit 50-BB12 (GY) and TR sensor C167-6, circuit 50-BB14 (GY/RD). Is the resistance less than 5 ohms? YES : Go to A7 . NO : REPAIR circuit 50-BB12 (GY)/50-BB14 (GY/RD) for an open. TEST the system for normal operation.
  7. A7 CHECK CIRCUIT 50-BB12 (GY)/50-BB2 (GY/BK) FOR AN OPEN Measure the resistance between starter motor C197-2, circuit 50-BB12 (GY)/50-BB2 (GY/BK) and TR sensor C167-9, circuit 50-BB12 (GY) Is the resistance less than 5 ohms? YES : Go to A8 . NO : REPAIR circuit 50-BB12 (GY)/50-BB2 (GY/BK) for an open. TEST the system for normal operation.
  8. A8 CHECK THE OPERATION OF TRANSMISSION RANGE (TR) SENSOR Measure the resistance between TR sensor C167-6, and -9 component side in PARK and NEUTRAL. Is the resistance less than 5 ohms? YES : INSTALL a new starter motor. TEST the system for normal operation. NO : ADJUST the TR sensor. If the concern persists, INSTALL a new TR sensor.

Under normal operation, the battery junction box (BJB) supplies constant power to the starter relay on circuit 30-BB9 (RD) through fuse F1.8 (30A). On vehicles with automatic transaxles, when the key is placed in the START position with the vehicle in PARK or NEUTRAL, the transmission range (TR) sensor provides power on circuit 50S-BB12 (GY)/50-BB2 (GY/BK) and the powertrain control module (PCM) provides ground on circuit 31S-BB16 (BK/RD). On vehicles with manual transaxles, when the key is placed in the START position with the clutch pedal depressed, the start inhibit switch provides power on circuit 50-BB12 (GY)/50-BB2 (GY/BK) and the PCM provides ground on circuit 31S-BB16 (BK/RD). The coil of the relay is energized and sends power to the starter motor on circuit 50-BB12 (GY)/50-BB2 (GY/BK).

Possible Causes

  1. Battery
  2. Open fuse
  3. Starter motor
  4. Ignition switch
  5. Clutch pedal position (CPP) switch (manual transaxle only)
  6. Circuitry
  7. Starter motor relay

Scheme 8

Scheme 8
Scheme 8

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Scheme 9
Scheme 9

Scheme 10

Scheme 10
Scheme 10

Scheme 11

Scheme 11
Scheme 11
  1. B1 CHECK THE CONDITION OF THE PATS SYSTEM Observe the PATS warning indicator. Does the indicator flash when attempting to start the vehicle? YES : REFER to «ANTI-THEFT - PASSIVE ANTI-THEFT SYSTEM (PATS)»(ref-278291) article to diagnose the PATS DTCs. NO : Go to B2 .
  2. B2 CHECK THE BATTERY Check the battery with a Midtronics tester. Carry out the battery capacity test using a scan tool. Is the battery OK? YES : Go to B3 . NO : INSTALL a new battery. REFER to «BATTERY, MOUNTING AND CABLES»(ref-278287) article. CHECK the battery with a Midtronics tester. TEST the system for normal operation.
  3. B3 CHECK THE SWITCHED POWER TO THE STARTER RELAY Key in ON position. Measure the voltage between central junction box (CJB) starter relay socket C2163-30, circuit 30-BB9 (RD) and ground. Is the voltage greater than 10 volts? YES : For automatic transaxle, go to B4 . For manual transaxle, go to B5 . NO : Go to B7 .
  4. B4 CHECK CIRCUIT 31S-BB16 (BK/RD) (AUTOMATIC TRANSAXLE ONLY) FOR AN OPEN Key in OFF position. Disconnect: PCM C175b Measure the resistance between CJB starter relay C2163-86, circuit 31S-BB16 (BK/RD) and PCM C175b-2, circuit 31S-BB16 (BK/RD). Is the resistance less than 5 ohms? YES : CARRY OUT the relay component test on the starter relay. Refer to appropriate COMPONENT TESTING article. If the relay tests as good, REFER to «INTRODUCTION - GASOLINE ENGINES»(ref-268480) article for PCM testing and replacement procedures. TEST the system for normal operation. NO : REPAIR circuit 31S-BB16 (BK/RD). TEST system for normal operation.
  5. B5 CHECK CIRCUIT 31S-BB16 (BK/RD) (MANUAL TRANSAXLE ONLY) FOR AN OPEN Key in OFF position. Disconnect: PCM C175b Depress the clutch pedal. Measure the resistance between CJB starter relay C2163-86, circuit 31S-BB16 (BK/RD) and PCM C175b-2, circuit 31S-BB16 (BK/RD). Is the resistance less than 5 ohms? YES : CARRY OUT the relay component test on the starter relay. Refer to appropriate COMPONENT TESTING article. If the relay tests as good, INSTALL a new PCM. TEST the system for normal operation. NO : Go to B6 .
  6. B6 CHECK THE START INHIBIT SWITCH FOR CORRECT OPERATION (MANUAL TRANSAXLE ONLY) Disconnect: Starter Switch C2195 Measure the resistance between start inhibit switch C2195-1 and -2. Is the resistance less than 5 ohms with the clutch pedal depressed and greater than 10,000 ohms with the clutch pedal released? YES : REPAIR circuit 31S-BB16 (BK/RD). TEST the system for normal operation. NO : INSTALL a new start inhibit switch. TEST the system for normal operation.
  7. B7 CHECK THE VOLTAGE TO IGNITION SWITCH CIRCUIT 30-BB9 (RD) Disconnect: Ignition Switch C250 Measure the voltage between ignition switch C250-4, circuit 30-BB9 (RD), harness side and ground. Is the voltage greater than 10 volts? YES : Go to B8 . NO : REPAIR circuit 30-BB9 (RD) for an open. TEST the system for normal operation. If the problem persists, REPAIR or INSTALL a new battery junction box.
  8. B8 CHECK CIRCUIT 50-BB16 (GY/BK) FOR AN OPEN Measure the resistance between ignition switch C250-7 circuit 50-BB16 (GY/BK) and CJB starter relay C2163-85, circuit 50-BB16 (GY/BK). Is the resistance less than 5 ohms? YES : INSTALL a new ignition switch. TEST the system for normal operation. NO : REPAIR circuit 50-BB16 (GY/BK) for an open. TEST the system for normal operation.

Under normal operation, the battery junction box (BJB) supplies constant power to the starter relay on circuit 30-BB9 (RD) through fuse F1.8 (30A). On vehicles with automatic transaxles, when the key is placed in the START position with the vehicle in PARK or NEUTRAL, the transmission range (TR) sensor provides power on circuit 50S-BB12 (GY) and the powertrain control module (PCM) provides ground on circuit 31S-BB16 (BK/RD). On vehicles with manual transaxles, when the key is placed in the START position with the clutch pedal depressed, the start inhibit switch provides power on circuit 50-BB12 (GY) and the PCM provides ground on circuit 31S-BB16 (BK/RD). The coil of the relay is energized and sends power to the starter motor on circuit 50-BB12 (GY).

Possible Causes

  1. Battery
  2. Starter motor
  3. Circuitry

Scheme 12

Scheme 12: PINPOINT TEST C: THE ENGINE CRANKS SLOWLY
Scheme 12: PINPOINT TEST C: THE ENGINE CRANKS SLOWLY

Scheme 13

Scheme 13
Scheme 13
  1. C1 CHECK THE BATTERY Check for loose connections at the battery positive and negative terminals. Check the battery with a Midtronics tester. Carry out the battery capacity test using a scan tool. Is the battery OK? YES : Go to C2 . NO : INSTALL a new battery. REFER to «BATTERY, MOUNTING AND CABLES»(ref-278287) article. CHECK the battery with a Midtronics tester. TEST the system for normal operation.
  2. C2 CHECK THE STARTER MOTOR LOAD Carry out the starter motor load test on the starter motor. Refer to «Starter Motor - Load Test»(ref-278248-S35057945842008012400000) . Is the starter motor OK? YES : Go to C2 . NO : INSTALL a new starter motor. REFER to «Starter Motor»(ref-278248-S06309259352008012400000) .
  3. C3 CHECK FOR A VOLTAGE DROP Measure the voltage between starter motor C197-2, component side and the positive battery terminal with the ignition switch in position III. Is the voltage less than 0.5 volt? YES : Go to C3 . NO : CLEAN and TIGHTEN all positive battery cable connections. TEST the system for normal operation. If the concern persists, INSTALL a new positive battery cable.
  4. C4 CHECK FOR A GROUND CONNECTION Measure the voltage between the starter motor case and battery negative terminal with the ignition switch in position III. Is the voltage less than 0.5 volt? YES : DIAGNOSE the battery and charging system. REFER to «CHARGING SYSTEM - GENERAL INFORMATION»(ref-278295) article. NO : CLEAN and TIGHTEN all negative battery cable connections, starter motor mounting and body to engine ground strap. TEST the system for normal operation. If the concern persists, INSTALL a new negative battery cable.

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