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Crankshaft Position (CKP) Sensor Malfunction

DTC P0320 DETECTION CONDITION AND POSSIBLE CAUSE

DTC P0320 CRANKSHAFT POSITION (CKP) SENSOR MALFUNCTION
DETECTION CONDITION 
  • P0320 indicates that two successive erratic Profile Ignition Pickup (PIP) pulses occurred resulting in possible engine miss or stall.
POSSIBLE CAUSE 
  • Loose wires/connectors.
  • Arcing secondary ignition components (coil, wires or plugs).
  • On-board transmitter (2-way radio).
  • CKP sensor.
HINT  Crankshaft Position Sensor Description 
  • Magnetic transducer mounted on engine block adjacent to a pulse wheel located on the crankshaft.
  • Monitors the crankshaft mounted pulse wheel which has 35 teeth spaced 10 degrees apart with one empty space.
    • Indicates crankshaft position and speed information to the PCM by monitoring the pulse wheel.
    • Identifies piston travel by monitoring the missing tooth in order to synchronize the ignition system and provide a way of tracking the angular position of the crankshaft relative to a fixed reference for the CKP sensor configuration.
    • The PCM also uses the CKP signal to determine if a misfire has occurred by measuring rapid deceleration between teeth.
G03988124Courtesy of MAZDA MOTORS CORP.
G03988125Courtesy of MAZDA MOTORS CORP.
DTC P0300, P0301, P302, P0303, P0304, P0305, P0306 INSPECTION

STEP INSPECTION ACTION
1
  • Was PCM Quick Test performed? 
 Yes Go to next step.
No Perform PCM Quick Test.
2 DTC P0320: ERRATIC IGNITION
  • Check for the following:
    • Loose wires/connectors.
    • Arcing secondary ignition components (coil, wires, plugs).
    • 2-way radio.
    NOTE: Verify all 2-way radio installations regarding the routing of antenna and power leads. Carefully follow manufacturer's installation instructions.
  • Are any of the above present? 
 Yes Repair as necessary.
Go to step 23.
No For No Starts:
See TEST 16: NO START .

For Intermittent Faults:


See TEST 4: INTERMITTENT .
All others:
Loss of PIP.
Go to step 2.
3 CHECK CKP(+)/CKP(-) CONTINUITY
  • Disconnect the CKP sensor and PCM.
  • Install Breakout Box, leave PCM disconnected.
  • Measure resistance of CKP(+) circuit between PCM test pin 21 and the CKP harness connector.
  • Measure resistance of CKP(-) circuit between PCM test pin 22 and the CKP harness connector.
  • Is each resistance greater than 5 ohms? 
 Yes Repair open circuit.
Go to step 23.
No Go to next step.
4 CHECK FOR CKP(+) BIAS VOLTAGE FAULT.
  • Remove Breakout Box.
  • Reconnect PCM.
  • Key ON, Engine OFF (KOEO).
  • Measure voltage between CKP(+) at the CKP harness connector and battery negative post.
  • Key OFF.
  • Was the voltage between 1.0 and 2.0 V? 
 Yes Go to next step.
No Bias fault. Go to step 17.
5 CHECK FOR CKP(-) BIAS VOLTAGE FAULT.
  • Key ON, Engine OFF (KOEO).
  • Measure voltage between CKP(-) at the CKP harness connector and battery negative post.
  • Key OFF.
  • Was the voltage between 1.0 and 2.0 V? 
 Yes Go to step 9.
No Bias fault.
Go to next step.
6 DETERMINE IF BIAS HIGH OR BIAS LOW FAULT
  • Was bias voltage reading for CKP(-) less than 1.0 V? 
 Yes Bias low fault.
Go to next step.
No Bias high fault.
Go to step 8.
7 CHECK FOR CKP(-) SHORT TO GROUND IN HARNESS
  • Disconnect PCM.
  • Install Breakout Box, leave PCM disconnected.
  • Measure resistance of CKP(-) circuit between PCM test pin 22 and battery negative post.
  • Is the resistance greater than 10K ohms? 
 Yes Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Go to step 23.
No Repair short circuit.
Go to step 23.
8 CHECK FOR CKP(-) SHORT TO POWER IN HARNESS
  • Disconnect PCM.
  • Install Breakout Box, leave PCM disconnected.
  • Key ON, Engine OFF (KOEO).
  • Measure voltage of CKP(-) circuit between PCM test pin 22 and battery negative post.
  • Is the voltage less than 0.5 V? 
 Yes Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Go to step 23.
No Repair short circuit.
Go to step 23.
9 CHECK CKP SENSOR AMPLITUDE AT PCM
  • Disconnect PCM.
  • Install Breakout Box, leave PCM disconnected.
  • Measure voltage between PCM test pin 21 (CKP(+)) and PCM test pin 22 (CKP(-)) while cranking engine.
  • Was settled AC voltage reading greater then 0.4 V? 
 Yes Go to next step
No Amplitude fault.
Go to step 11.
10 CHECK CKP(+) CIRCUIT FOR SHORT TO GROUND AT SENSOR
  • Measure resistance between test pin 21 and battery negative post.
  • Is the resistance greater than 10K ohms? 
 Yes Go to step 20.
No Go to step 15.
11 CHECK CKP CIRCUIT RESISTANCE FOR AMPLITUDE FAULT
  • Measure resistance between PCM test pin 21 (CKP(+)) and PCM test pin 22 (CKPB).
  • Is the resistance between 300 and 800 ohms? 
 Yes Go to step 14.
No Go to next step.
12 DETERMINE IF RESISTANCE HIGH OR RESISTANCE LOW FAULT
  • Was the resistance between CKP(+) and CKP(-) less than 300 ohms? 
 Yes Low resistance fault.
Go to next step.
No Replace CKP sensor.
Go to step 23.
13 CHECK CKP(+) FOR SHORT TO CKP(-)
  • Disconnect CKP sensor.
  • Measure resistance between CKP(+) and CKP(-) at the CKP harness connector.
  • Is the resistance less than 5 ohms? 
 Yes Repair short.
See IGNITION SYSTEM .
Go to step 23.
No Replace CKP sensor.
Go to step 23.
14 CHECK CKP SENSOR AND PULSE WHEEL
  • Visually inspect pulse wheel and CKP sensor for damage.
  • Are CKP sensor and pulse wheel OK? 
 Yes Replace CKP sensor.
Go to step 23.
No Repair or replace damaged parts.
Go to step 23.
15 CHECK FOR OPEN OR SHORT IN PCM
  • Disconnect CKP sensor.
  • Remove Breakout Box.
  • Reconnect PCM.
  • Measure resistance between CKP(+) and CKP(-) at the CKP harness connector.
  • Is the resistance between 16K and 24K ohms? 
 Yes Go to next step.
No Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Go to step 23.
16 CHECK CKP(+) FOR SHORT TO CKP(-)
  • Measure resistance between CKP(+) and CKP(-) at the CKP harness connector.
  • Is the resistance greater than 1K ohms? 
 Yes Replace CKP sensor.
Go to step 23.
No Repair short circuit.
See IGNITION SYSTEM .
Go to step 23.
17 DETERMINE IF BIAS VOLTAGE HIGH OR BIAS VOLTAGE LOW FAULT
  • Was bias voltage measured less than 1.0 volt? 
 Yes Low bias fault.
Go to next step.
No High bias fault.
Go to step 19.
18 CHECK CKP(+) CIRCUIT FOR SHORT TO GROUND IN HARNESS
  • Disconnect PCM.
  • Install Breakout Box, leave PCM disconnected.
  • Measure resistance between PCM test pin 21 (CKP(+) and battery negative post.
  • Is the resistance greater than 10K ohms? 
 Yes Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Go to step 23.
No Repair short circuit.
Go to step 23.
19 CHECK CKP(+) CIRCUIT FOR SHORT TO POWER IN HARNESS
  • Disconnect PCM.
  • Install Breakout Box, leave PCM disconnected.
  • Key ON, Engine OFF (KOEO).
  • Measure voltage between PCM test pin 21 (CKP(+)) and battery negative post.
  • Is the voltage less than 0.5 volts? 
 Yes Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Go to step 23.
No Repair short circuit.
Go to step 23.
20 VISUAL INSPECTION OF IGNITION SYSTEM
  • Visually inspect the engine compartment to make sure all coils and spark plug wires are secured properly.
  • Examine all wiring harnesses and connectors for damaged, burned or overheated insulation and loose or broken connections.
  • Make sure the battery is fully charged.
  • Verify all accessories or off.
  • Is a problem indicated? 
 Yes Repair as necessary.
Go to step 23.
No Go to next step.
21 DTC P0301 THROUGH DTC P0306: MISFIRE ON SPECIFIC CYLINDER
  • Are DTCs P0301 - P0306 present? 
 Yes Go to applicable DTC.
No Go to next step.
22 CHECK FOR SPARK AT ALL CYLINDERS
  • Disable inertia fuel shutoff switch.
  • Check for spark at each cylinder while cranking engine.
  • Is the bluish white spark consistent between all cylinders? 
 Yes Key OFF
Go to next step.
No Key OFF.
Inspect spark plug wires. Measure resistance of spark plug wires and replace them if greater then 7K ohms per 1 foot (30.5 cm).
Go to step 23.
22 CHECK SPARK PLUGS
  • Remove and inspect plugs for damage, wear, carbon deposits and proper plug gap.
  • Are plugs OK? 
 Yes Go to next step.
No Repair spark plugs or adjust gap. Replace if necessary.
Go to step 23.
22 CHECK SPARK PLUG RESISTANCE
  • Measure spark plug resistance.
  • Is resistance between 2K and 20K ohms? 
 Yes Fault is intermittent.
See TEST 4: INTERMITTENT .
No Replace spark plugs.
Go to step 23.
23 VERIFY TROUBLESHOOTING OF DTCs COMPLETED
  • Make sure to reconnect all disconnected connectors.
  • Clear DTCs from PCM memory using NGS tester generic OBD-II function.
  • Perform PCM Quick Test.
  • Is same DTC present? 
 Yes Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Repeat PCM Quick Test.
No If any other DTC is present, go to applicable DTC inspection.
If no DTC is present, troubleshooting complete.
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