Home/Ford/C-MAX/Ford C-MAX II (2010-2015)/Repair manual/Testing & Diagnostics/Engine Controls - Symptom Charts (Hybrid): Diagnosis
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Engine Controls - Symptom Charts (Hybrid): Diagnosis Ford C-MAX II

QT1 CARRY OUT THE NETWORK TEST

WARNINGTO PREVENT THE RISK OF HIGH-VOLTAGE SHOCK, ALWAYS FOLLOW PRECISELY ALL WARNINGS AND SERVICE INSTRUCTIONS, INCLUDING INSTRUCTIONS TO DEPOWER THE SYSTEM. THE HIGH-VOLTAGE HYBRID SYSTEM UTILIZES APPROXIMATELY 300 VOLTS DC, PROVIDED THROUGH HIGH-VOLTAGE CABLES TO ITS COMPONENTS AND MODULES. THE HIGH-VOLTAGE CABLES AND WIRING ARE IDENTIFIED BY ORANGE HARNESS TAPE OR ORANGE WIRE COVERING. ALL HIGH-VOLTAGE COMPONENTS ARE MARKED WITH HIGH-VOLTAGE WARNING LABELS WITH A HIGH-VOLTAGE SYMBOL. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN SERIOUS PERSONAL INJURY OR DEATH.
  1. Carry out all the safety steps required to run the vehicle tests.
  2. Complete the preliminary checks looking for obvious concerns that may relate to the symptom. Check items such as those listed: fuses electrical circuits and connectors vacuum lines (leaks, routing) intake air system (leaks, restrictions) fuel quality engine cooling system (engine operating at correct temperature) motor electronics cooling system
  3. Access any related OASIS or TSB information.
  4. Carry out the network test.

Does the network test pass?

YesNo
GO to Quick Test QT2 .For only the PCM has a communication concern, GO to PINPOINT TEST QA: UNABLE TO ACTIVATE SELF-TEST/NETWORK COMMUNICATION ERROR . For only the SOBDMC has a communication concern, GO to PINPOINT TEST QD: UNABLE TO ACTIVATE TRANSMISSION CONTROL MODULE (TCM) SELF-TEST . For all others, GO to the Module Communications Network article, to diagnose the network concern.

QT2 CARRY OUT THE PCM AND SOBDMC QUICK TEST

Note. Make sure the low voltage battery is fully charged and the low voltage system is operating correctly. Low voltage concerns may be a possible cause of a DTC.

Note. Do not carry out consecutive quick tests without turning the ignition to OFF position for a minimum of 15 seconds.

  1. Complete the PCM quick test to access any DTCs. Note any key ON engine OFF (KOEO), key ON engine running (KOER) (if engine runs) and continuous memory (MIL and non-MIL) DTCs.
  2. Complete the SOBDMC quick test to access any DTCs. Note any KOEO and continuous memory DTCs.

Are any PCM or SOBDMC DTCs present?

YesNo
GO to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS AND DESCRIPTIONS for direction to REPAIR any DTCs after noting the following: DIAGNOSE the PCM circuit related DTCs first. For multiple circuit DTCs that are set as a result of a concern with more than one component, REFER to the OEM Wiring Diagrams article and identify the common cause such as SIGRTN, VREF, or VPWR. DIAGNOSE the SOBDMC circuit related DTCs before system related range or performance DTCs. For multiple circuit DTCs that are set as a result of a concern with more than one component, REFER to the OEM Wiring Diagrams article and identify the common cause such as SIGRTN, VREF, or VPWR.GO to No Diagnostic Trouble Codes (DTCs) Present Symptom Chart Index for direction to the correct symptom chart in No Diagnostic Trouble Codes (DTCs) Present Symptom Charts . NOTE: If the symptom is not listed, REFER to the applicable service information or GO to PINPOINT TEST Z: INTERMITTENT (for intermittent PCM or SOBDMC system diagnostics).
NOTE
If the symptom is not listed, REFER to the applicable service information or GO to PINPOINT TEST Z: INTERMITTENT (for intermittent PCM or SOBDMC system diagnostics).

NO DIAGNOSTIC TROUBLE CODES (DTCS) PRESENT SYMPTOM CHART INDEX

System/SymptomOasis NumberChart Number
Engine/Vehicle Starting ConcernsNo Start/Vehicle DisabledChart 2
No Start/Normal CrankChart 3
Unique Idle ConcernsRolling IdleChart 1

DRIVEABILITY

System/SymptomOasis NumberChart Number
Stalls/QuitsIdle, Acceleration, CruiseChart 1
Engine Runs RoughChart 1
Engine MissesChart 1
Buck/JerkChart 1
Hesitation/StumbleChart 1
SurgeChart 1
Engine BackfiresChart 4
Lack/Loss of PowerChart 5
Engine Spark KnockChart 6

DRIVEABILITY - PERFORMANCE WHILE DRIVING CONCERNS

Note. OASIS identifiers (the x means any number (1-9) can be used) xxx4xx=during idle, xxx5xx=during acceleration, xxx6xx=during cruise, xxx7xx=during deceleration.

System/SymptomOasis NumberChart Number
Poor Fuel EconomyChart 7
Emissions ComplianceChart 8

ADDITIONAL DRIVEABILITY CONCERNS

System/SymptomOasis NumberChart Number
Warning IndicatorsMalfunction Indicator Lamp (MIL)Chart 9
Hazard Indicator LampChart 9
Powertrain Malfunction Indicator (Wrench) LampChart 9
Temperature Warning Indicator LampChart 9
Check Fuel Cap IndicatorChart 9

ELECTRICAL

System/SymptomOasis NumberChart Number
Oil System ConcernsHigh Oil ConsumptionChart 10
LeaksChart 10
Cooling System ConcernsElectric Engine Cooling Fan Does Not OperateChart 11
Electric Engine Cooling Fan Always RunsChart 12
Exhaust System ConcernsVisible SmokeChart 13
Odor (Sulfur Or Rotten Egg Smell)Chart 16
Fuel System ConcernsFuel Odor, Engine CompartmentChart 14
Engine Noise (Under Hood)Chart 15

ENGINE