Starting System: Overview — Ford Escape I facelift 2 (2007-2012)

Normal Operation

Under normal operation, the Battery Junction Box (BJB) supplies constant power to the starter motor relay on circuit SBB11 (BU/RD) through fuse 11 (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 sends a signal to the PCM and provides ground to the starter motor relay. On vehicles with manual transaxles, when the key is placed in the START position with the clutch pedal depressed, the clutch cutoff switch sends a signal to the PCM and provides ground to the starter motor relay. This allows power to be supplied from the starter motor relay contacts which then flows through circuit CDC25 (BN/GN) to the starter solenoid. The solenoid is grounded at the starter motor. Energizing the starter solenoid will engage the starter drive into the ring gear and closes the solenoid contacts, allowing power directly from the battery through circuit SDC02 (RD) to the starter motor to start the engine.

This pinpoint test is intended to diagnose the following

Battery
Anti-theft system
Starter relay
Ignition switch
Circuitry
TR sensor (automatic transaxle)
Clutch cutoff switch (manual transaxle)
PCM
Start diode

Scheme 1

Scheme 1: PINPOINT TEST A: THE ENGINE DOES NOT CRANK

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 11

Scheme 12

Scheme 13

Scheme 14

Scheme 15

Scheme 16

A1 CHECK THE BATTERY Check the battery condition and state of charge. Refer to Diagnosis and Testing in «BATTERY, MOUNTING AND CABLES»(ref-344091) . Is the battery OK? Yes: GO to A2 . No: CHARGE or INSTALL a new battery as necessary. REFER to «BATTERY, MOUNTING AND CABLES»(ref-344091) . TEST the system for normal operation.
A2 CHECK FOR PCM DTCs Using the DTCs retrieved in Inspection and Verification, check for PCM DTCs. Were any PCM DTCs retrieved? Yes: If PCM DTC P1260 is retrieved, REFER to «ANTI-THEFT - PATS - HYBRID»(ref-344128) . All other PCM DTCs, REFER to «INTRODUCTION - GASOLINE MODELS»(ref-342225) . No: For automatic transmission, GO to A3 . For manual transmission, GO to A4 .
A3 CHECK THE PCM AUTOMATIC TR SENSOR PID Connect the scan tool. Ignition ON. Enter the following diagnostic mode on the scan tool: DataLogger - PCM. While observing the TR sensor PID, place the vehicle in PARK and NEUTRAL. Does the PID match the gear selection? Yes: GO to A5 . No: GO to the «AUTOMATIC TRANSAXLE/TRANSMISSION - 6F35»(ref-344057) .
A4 CHECK THE PCM CLUTCH PEDAL AT OR NEAR BOTTOM OF TRAVEL (CPP___BOT) PID Connect the scan tool. Ignition ON. Enter the following diagnostic mode on the scan tool: DataLogger - PCM. While observing the CPP___BOT PID, fully disengage the clutch. Does the PID change from NO to YES? Yes: GO to A5 . No: GO to A25 .
A5 CHECK THE STARTER MOTOR CONTROL OUTPUT DETECTED (SMC___MON) PID Connect the scan tool. Ignition ON. Enter the following diagnostic mode on the scan tool: DataLogger - PCM. NOTE: For manual transaxle, fully disengage the clutch. Monitor the PID SMC___MON PID with the ignition switch in the START position. Does the PID change from OFF to ON? Yes: GO to A6 . No: GO to A13 .
A6 CHECK THE STARTER MOTOR RELAY ENABLE (STRT___RLY) PID Connect the scan tool. Ignition ON. Enter the following diagnostic mode on the scan tool: DataLogger - PCM. NOTE: For manual transaxle, fully disengage the clutch. Monitor the PID STRT___RLY PID with the ignition switch in the START position. Does the PID change from DISABLED to ENABLED? Yes: GO to A7 . No: GO to A22 .
A7 CHECK FOR VOLTAGE TO THE STARTER MOTOR RELAY NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector. Ignition OFF. Disconnect: Starter Motor Relay. Measure the voltage between BJB starter motor relay pin 3, circuit SBB11 (BN/RD) and ground. Is the voltage greater than 10 volts? Yes: GO to A8 . No: VERIFY BJB fuse 11 (30A) is OK. If OK, REPAIR the circuit SBB11 (BN/RD). TEST the system for normal operation. If not OK, REFER to the «SYSTEM WIRING DIAGRAMS - ESCAPE»(ref-311193) or «SYSTEM WIRING DIAGRAMS - MARINER»(ref-311218) to identify the possible causes of the circuit short.
A8 CHECK THE BATTERY GROUND CABLE Measure the voltage between the positive battery post and the battery ground cable connection at the engine. Is the voltage greater than 10 volts? Yes: GO to A9 . No: INSTALL a new battery ground cable. REFER to «BATTERY, MOUNTING AND CABLES»(ref-344091) . TEST the system for normal operation.
A9 CHECK STARTER MOTOR GROUND Measure the voltage between the positive battery post and the starter motor case. Is the voltage greater than 10 volts? Yes: GO to A10 . No: CLEAN the starter motor mounting flange and make sure the starter motor is correctly mounted. TEST the system for normal operation.
A10 CHECK THE POWER SUPPLY TO THE STARTER MOTOR Measure the voltage between starter motor C197A, circuit SDC02 (RD) and ground. Is the voltage greater than 10 volts? Yes: GO to A11 . No: INSTALL a new positive battery cable. REFER to «BATTERY, MOUNTING AND CABLES»(ref-344091) . TEST the system for normal operation.
A11 CHECK THE STARTER MOTOR B-PIN Connect one end of a fused jumper wire to starter motor C197A, circuit SDC02 (RD). Momentarily connect the other end of the jumper to starter motor C197B, circuit CDC25 (BN/GN). Did the starter motor engage and the engine crank? Yes: GO to A12 . No: INSTALL a new starter motor. REFER to «STARTER MOTOR - 2.5L»(ref-344115-S10365805232009101600000) or «STARTER MOTOR - 3.0L»(ref-344115-S34452857682009101600000) . TEST the system for normal operation.
A12 CHECK THE CIRCUIT TO THE STARTER MOTOR NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector. Ignition OFF. Disconnect: Starter Motor Solenoid C197B. Disconnect: Starter Motor Relay. Measure the resistance between starter motor C197B, circuit CDC25 (BN/GN) and BJB starter relay pin 5, circuit CDC25 (BN/GN). Is the resistance less than 5 ohms? Yes: INSTALL a new starter motor relay. TEST the system for normal operation. No: REPAIR the circuit CDC25 (BN/GN). TEST the system for normal operation.
A13 CHECK FOR VOLTAGE TO THE STARTER MOTOR RELAY NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector. Ignition OFF. Disconnect: Starter Motor Relay. Measure the voltage between BJB starter motor relay pin 3, circuit SBB11 (BN/RD) and ground. Is the voltage greater than 10 volts? Yes: GO to A14 . No: VERIFY BJB fuse 11 (30 A) is OK. If OK, REPAIR the circuit SBB11 (BN/RD). TEST the system for normal operation. If not OK, REFER to the «SYSTEM WIRING DIAGRAMS - ESCAPE»(ref-311193) or «SYSTEM WIRING DIAGRAMS - MARINER»(ref-311218) to identify the possible causes of the circuit short.
A14 CHECK THE STARTER MOTOR RELAY Carry out the Starter Motor Relay Component Test. Refer to «SYSTEM WIRING DIAGRAMS - ESCAPE»(ref-311193) or «SYSTEM WIRING DIAGRAMS - MARINER»(ref-311218) for component testing. Did the starter motor relay pass the component test? Yes: GO to A15 . No: INSTALL a new starter motor relay. TEST the system for normal operation.
A15 CHECK THE START DIODE Disconnect: Start Diode. Check the start diode for an open or shorted condition. Is the start diode OK? Yes: GO to A16 . No: INSTALL a new start diode. TEST the system for normal operation.
A16 CHECK CIRCUIT CDC54 (WH/GN) FOR VOLTAGE NOTE: For manual transaxle, fully disengage the clutch. Connect: Start Diode. Measure the voltage between BJB starter motor relay pin 2, circuit CDC54 (WH/GN) and ground with the ignition switch in the START position. Is the voltage greater than 10 volts? Yes: GO to A19 . No: GO to A17 .
A17 CHECK CIRCUIT SBP27 (BU/RD) FOR VOLTAGE Disconnect: Ignition Switch C250. Measure the voltage between ignition switch C250-4, circuit SBP27 (BU/RD), harness side and ground. Is the voltage greater than 10 volts? Yes: GO to A18 . No: VERIFY Smart Junction Box (SJB) fuse 27 (20 A) is OK. If OK, REPAIR circuit SBP27 (BU/RD). TEST the system for normal operation. If not OK, REFER to the «SYSTEM WIRING DIAGRAMS - ESCAPE»(ref-311193) or «SYSTEM WIRING DIAGRAMS - MARINER»(ref-311218) to identify the possible causes of the circuit short.
A18 CHECK THE IGNITION SWITCH Carry out the Ignition Switch Component Test. Refer to «SYSTEM WIRING DIAGRAMS - ESCAPE»(ref-311193) or «SYSTEM WIRING DIAGRAMS - MARINER»(ref-311218) for component testing. Did the ignition switch pass the component test? Yes: REPAIR circuit CDC35 (BU/WH). TEST the system for normal operation. No: INSTALL a new ignition switch. REFER to «STEERING COLUMN SWITCHES»(ref-344080) . TEST the system for normal operation.
A19 CHECK CIRCUIT CDC54 (WH/GN) FOR AN OPEN Disconnect: Start Diode. Disconnect: PCM C175B. Measure the resistance between BJB start diode cell, circuit CDC54 (WH/GN), harness side and PCM C175B-37, circuit CDC54 (WH/GN), harness side. Is the resistance less than 5 ohms? Yes: GO to A20 . No: REPAIR circuit CDC54 (WH/GN). TEST the system for normal operation.
A20 CHECK THE START SIGNAL TO THE STARTER MOTOR RELAY Connect: Start Diode. Disconnect: Starter Motor Relay. Measure the resistance between BJB starter motor relay pin 2, circuit CDC54 (WH/GN), harness side and C175B-37, circuit CDC54 (WH/GN), harness side. Is the resistance less than 5 ohms? Yes: GO to A21 . No: REPAIR circuit CDC54 (WH/GN). TEST the system for normal operation.
A21 CHECK CIRCUIT CDC35 (BU/WH) FOR AN OPEN Connect: Starter Motor Relay. Measure the resistance between BJB start diode cell, circuit CDC35 (BU/WH), harness side and PCM C175B-16, circuit CDC35 (BU/WH), harness side. Is the resistance less than 5 ohms? Yes: INSTALL a new PCM. REFER to «ELECTRONIC ENGINE CONTROLS - 2.5L»(ref-344104) or «ELECTRONIC ENGINE CONTROLS - 3.0L (4V)»(ref-344105) . TEST the system for normal operation. No: REPAIR circuit CDC35 (BU/WH). TEST the system for normal operation.
A22 CHECK FOR VOLTAGE TO THE STARTER MOTOR RELAY NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector. Ignition OFF. Disconnect: Starter Motor Relay. Measure the voltage between BJB starter motor relay pin 3, circuit SBB11 (BN/RD) and ground. Is the voltage greater than 10 volts? Yes: GO to A23 . No: VERIFY BJB fuse 11 (30 A) is OK. If OK, REPAIR the circuit SBB11 (BN/RD). TEST the system for normal operation. If not OK, REFER to the «SYSTEM WIRING DIAGRAMS - ESCAPE»(ref-311193) or «SYSTEM WIRING DIAGRAMS - MARINER»(ref-311218) to identify the possible causes of the circuit short.
A23 CHECK THE STARTER MOTOR RELAY Carry out the Starter Motor Relay Component Test. Refer to «SYSTEM WIRING DIAGRAMS - ESCAPE»(ref-311193) or «SYSTEM WIRING DIAGRAMS - MARINER»(ref-311218) for component testing. Did the starter motor relay pass the component test? Yes: GO to A24 . No: INSTALL a new starter motor relay. TEST the system for normal operation.
A24 CHECK CIRCUIT CDC12 (YE) FOR AN OPEN Ignition OFF. Disconnect: PCM C175B. Disconnect: Starter Motor Relay. Measure the resistance between BJB starter motor relay pin 1, circuit CDC12 (YE), harness side and PCM C175B-7, circuit CDC12 (YE), harness side. Is the resistance less than 5 ohms? Yes: INSTALL a new PCM. REFER to «ELECTRONIC ENGINE CONTROLS - 2.5L»(ref-344104) or «ELECTRONIC ENGINE CONTROLS - 3.0L (4V)»(ref-344105) . TEST the system for normal operation. No: REPAIR circuit CDC12 (YE). TEST the system for normal operation.
A25 CHECK CIRCUIT GD120 (BK/GN) FOR AN OPEN Ignition OFF. Disconnect: Clutch Cutoff Switch C2072. Measure the resistance between clutch cutoff switch C2072-1, circuit GD120 (BK/GN), harness side and ground. Is the resistance less than 5 ohms? Yes: GO to A26 . No: REPAIR circuit GD120 (BK/GN). TEST the system for normal operation.
A26 CHECK CIRCUIT CE903 (BU/OG) FOR AN OPEN Ignition OFF. Disconnect: PCM C175T. Measure the resistance between clutch cutoff switch C2072-2, circuit CE903 (BU/OG), harness side and PCM C175T-26, circuit CE903 (BU/OG), harness side. Is the resistance less than 5 ohms? Yes: GO to A27 . No: REPAIR circuit CE903 (BU/OG). TEST the system for normal operation.
A27 CHECK CLUTCH CUTOFF SWITCH FOR AN OPEN Measure the resistance between clutch cutoff switch C2072-2 and C2072-1, component side, fully disengage the clutch. Is the resistance less than 5 ohms? Yes: INSTALL a new PCM. REFER to «ELECTRONIC ENGINE CONTROLS - 2.5L»(ref-344104) or «ELECTRONIC ENGINE CONTROLS - 3.0L (4V)»(ref-344105) . TEST the system for normal operation. No: REPLACE the clutch cutoff switch. NOTE: The clutch cutoff switch is self-adjusting and will adjust the first time the pedal is pushed. DO NOT push on the plunger of the new switch prior to installation or damage to the switch may occur. TEST the system for normal operation.

When the ignition switch is turned to the START position and released, the PCM receives a starter motor request signal through circuit CDC35 (BU/WH). Power is then supplied from the PCM to the starter motor relay through circuit CDC54 (WH/GN). A ground is supplied through circuit CDC12 (YE) from the PCM causing the starter motor relay coil to energize and the relay contacts close. This allows power from starter motor relay through circuit CDC25 (BN/GN) to the starter solenoid. The solenoid is grounded at the starter motor. Energizing the starter solenoid will engage the starter drive into the ring gear and closes the solenoid contacts allowing power directly from the battery through circuit SDC02 (RD) to the starter motor to start the engine. The customer is no longer in the loop after the initial crank request, the customer may release the key to the RUN/START position. The PCM will disengage the starter motor based on engine running (RPM threshold), a set crank time has been exceeded or the ignition switch has been turned to the OFF position.