OBD II MONITORING CONDITIONS
When testing for DTC reoccurrence, it can be determined if the Service Drive Cycle was of sufficient length by performing a PDU "Systems Readiness Test".
The Systems Readiness Test occurs automatically when DTC retrieval is initiated.
If DTC P1000 is stored in memory, the on-board diagnostic tests have not been completed. If DTC P1111 is stored in memory, all on-board diagnostic tests have been completed.
To identify which portions of the Systems Readiness Test have not been completed, access OBD Logger from PDU Toolbox. PDU will report in the following manner
- Module ECM
The following tests have been identified as incomplete
Catalyst
Evaporative purge system
O2 Sensor
EGR system
Refer to the following for important information regarding the use of this Summary.
MONITORING CONDITIONS
"SERVICE DRIVE CYCLE" For the particular DTC. Operate the vehicle as described to check for a reoccurrence of the DTC.
PDU DATALOGGER ACRONYMS
ACCREQ: A/C compressor clutch request
ACHPS: A/C refrigerant high pressure switch
ACLPS: A/C refrigerant low pressure switch
ADV: Ignition timing advance (Cyl 1, A bank)
BARO: Barometric pressure sensor
BAT1+: Battery B+ supply to ECM
CLV: Calculated load value
CRANKREQ: Crank request (from BPM)
CRUISEA: Cruise control accel/decel switch
CRUISEB: Cruise resume/cancel switch
CRUISEC: Cruise cancel switch
CRUISED: Cruise control set/inch/decel switch
CRUISEO: Cruise control ON/OFF switch
CRUISER: Cruise control resume switch
CRUISES: Cruise control set/inch/accel switch
CRUISEC1: Cruise control cancel switch
DTC1: Number of DTCs logged this trip
DTCS: Number of permanent DTCs logged
ECT: Engine coolant temperature
EGR: Exhaust gas recirculation
EVAP: Evaporative emission system monitor
FANF: Cooling fan fast
FANFRLY: Cooling fan relay fast
FANS: Cooling fan slow
FANSRLY: Cooling fan relay slow
FBRAKE2: Brake switch
FP: Fuel pump
FPRLY: Fuel pump relay
GUARD1: Mechanical guard sensor
O2SB1D: Oxygen sensor (downstream) A bank
O2SB2D: Oxygen sensor (downstream) B bank
HO2SB1U: Heated oxygen sensor (upstream) A bank
HO2SB2U: Heated oxygen sensor (upstream) B bank
HTDSC: Heated windshield request
IAT: Intake air temperature
KS1A: Knock sensor 1 A bank
KS1B: Knock sensor 1 B bank
KS4A: Knock sensor 4 A bank
KS4B: Knock sensor 4 B bank
KSFA: Knock sensor fail A bank
KSFB: Knock sensor fail B bank
LTFT1: Long term fuel trim A bank
LTFT2: Long term fuel trim B bank
MAF: Mass air flow
MAFGND1: MAFS ground
MAFS1: Mass air flow sensor
MPROBE: Measurement probe (RED)
PKBRAKE: Park brake switch
PNPS: Park/neutral position switch (rotary switch)
PPS1: Pedal position sensor track A
PPS2: Pedal position sensor track B
RPM: Engine speed
SPS: Sensor power supply monitor
STFT1: Short term fuel trim A bank
STFT2: Short term fuel trim B bank
STFTB1D: Short term fuel trim A bank downstream
STFTB1U: Short term fuel trim A bank upstream
STFTB2D: Short term fuel trim B bank downstream
STFTB2U: Short term fuel trim B bank upstream
TPS: Throttle position sensor
TPS1: Throttle position sensor track 1
TPS2: Throttle position sensor track 2
TTP: Target throttle position
VSS: Vehicle speed
VSVRM: Vacuum switching valve release monitor
VSVAM: Vacuum switching valve atmosphere monitor
VSVVM: Vacuum switching valve vacuum monitor
VVTBM: Variable valve timing (B bank) monitor
Engine at normal operating temperature; drive 43 - 59 mph (70 - 95 km/h); 1500 - 2500 rpm; > 10 seconds
OBD II
Y
OK ENG
2
OTHER
2 [A, M]
DEFAULT ACTION
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Substitutes throttle angle for engine load measurement
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR
POSSIBLE CAUSES
Blocked air cleaner
Air intake leak
Engine breather leak
Throttle control malfunction (TPS)
MAFS to ECM sensing circuit high resistance
MAFS to ECM sensing circuit intermittent short circuit to ground
MAFS supply circuit high resistance
MAFS failure
Ignition ON > 5 seconds
Y
2
1 [A, M]
When AMBER MIL is activated (DTC logged; first trip), ECM
- Substitutes throttle angle for engine load measurement
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR
Blocked air filter
MAFS to ECM sensing circuit high resistance or open circuit
MAFS to ECM sensing circuit intermittent short circuit to ground
MAFS supply circuit open circuit or short circuit to ground
MAFS failure
Ignition ON > 5 seconds
Y
2
1
When AMBER MIL is activated [A, M] (DTC logged; first trip), ECM
- Substitutes throttle angle for engine load measurement
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR
MAFS to ECM reference ground circuit open circuit
MAFS to ECM sensing circuit short circuit to high voltage
MAFS failure
Ignition ON > 5 seconds
Y
2
N
None
BARO failure (internal ECM fault)
Ignition ON > 5 seconds
Y
2
N
None
BARO failure (internal ECM fault)
Engine idle > 40 seconds
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Substitutes fixed temperature of 50 °C (122 °F)
Blocked air cleaner
Air intake leak
Engine breather leak
IATS to ECM wiring open circuit or high resistance
IATS to ECM sensing circuit short circuit to high voltage
IATS failure
Ignition ON > 5 seconds
Y
2
N
When DTC is logged (first trip), ECM
- Substitutes fixed temperature of 50 °C (122 °F)
IATS to ECM wiring open circuit or high resistance
IATS to ECM sensing circuit short circuit to high voltage
IATS failure
Ignition ON > 5 seconds
Y
2
N
When DTC is logged (first trip), ECM
- Substitutes fixed temperature of 50 °C (122 °F)
IATS to ECM wiring short circuit to ground
IATS failure
Engine coolant temperature ambient; start engine; drive at normal operating temperature > 13 mph (20 km/h) > 3 minutes
Y
2
2 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Substitutes transmission fluid temperature (via CAN
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR
- Inhibits VVT
Low coolant level
Contaminated coolant
Engine thermostat failure
ECTS to ECM sensing circuit high resistance when hot
ECTS to ECM sensing circuit intermittent high resistance
ECTS failure
Ignition ON > 5 seconds
Y
2
1 [A, M]
When AMBER MIL is activated (DTC logged; first trip), ECM
- Substitutes transmission fluid temperature (via CAN
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR
- Inhibits VVT
ECTS disconnected
ECTS to ECM sensing circuit high resistance, open circuit or short circuit to high voltage
ECTS failure
Ignition ON > 5 seconds
Y
2
1 [A, M]
Refer to P0117 Default Action
Engine overheat condition
ECTS to ECM wiring short circuit to ground
ECTS failure
Ignition ON > 5 seconds
Y
2
1 [R, M]
When RED MIL is activated (DTC logged; first trip), ECM
- Defaults throttle to mechanical guard mode
- Inhibits idle speed control
- Inhibits cruise control
- Inhibits traction control/stability control
- Inhibits power limiting
TPS to ECM wiring open circuit or high resistance TPS to ECM sensing circuits ("1" or "2") short circuit to high voltage
TPS failure
Ignition ON > 5 seconds
Y
2
1 [R, M]
Refer to P0121 Default Action
TPS to ECM sensing circuit "1" (TPS pin 3) open circuit or high resistance
TPS failure
Ignition ON > 5 seconds
Y
2
1 [R, M]
Refer to P0121 Default Action
TPS to ECM sensing circuit "1" (TPS pin 3) short circuit to high voltage
TPS failure
Engine coolant temperature ambient; start engine; run engine to > 60 °C (140 °F) > 2 minutes
Y
2
1 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Substitutes transmission fluid temperature (via CAN)
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR
- Inhibits VVT
Low coolant level
Contaminated coolant
Engine thermostat failure
ECTS to ECM sensing circuit high resistance, open circuit or short circuit to high voltage
Engine at normal operating temperature; drive at steady speed > 40 mph (60 km/h); engine speed 1300 - 4500 rpm > 1 minute 20 seconds
Y
2
N
None
HO2S disconnected
HO2S to ECM wiring open circuit
HO2S short circuit to ground
HO2S failure
Engine at normal operating temperature; drive at steady speed > 3 mph (4 km/h)
Y
2
N
None
HO2S sensing circuit short circuit to high voltage
HO2S ground (BRD - braided shield) open circuit
HO2S failure
Engine at normal operating temperature; drive at 50 - 62 mph (80 - 100 km/h); engine speed 1500 - 2500 rpm >10 seconds
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits A bank closed loop fuel metering
- Inhibits A bank adaptive fuel metering
Engine misfire
HO2S disconnected
HO2S mechanical damage
HO2S to ECM wiring intermittent open circuit
HO2S sensing circuit short circuit to high voltage
HO2S short circuit to ground
HO2S ground (BRD - braided shield) open circuit
HO2S heater circuit fault
Exhaust leak
Low exhaust temperature
Injector flow partially blocked
Catalyst efficiency decrease
HO2S failure
Engine at normal operating temperature; drive at steady speed > 20 mph (30 km/h)
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits A bank closed loop fuel metering
- Inhibits A bank adaptive fuel metering
- Inhibits A bank downstream O2S control
HO2S disconnected
HO2S heater power supply open circuit
HO2S heater to ECM wiring short circuit or open circuit
HO2S heater failure
Ambient temperature < 70 °C (158 °F); engine at normal operating temperature; drive at steady speed > 13 mph (20 km/h) > 1 minute 10 seconds
Y
2
N
None
O2S disconnected
O2S to ECM wiring open circuit
O2S short circuit to ground
O2S failure
Ambient temperature < 70 °C (158 °F); engine at normal operating temperature; drive at steady speed > 13 mph (20 km/h) > 1 minute 10 seconds
Y
2
N
None
O2S sensing circuit short circuit to high voltage
O2S ground (BRD - braided shield) open circuit
O2S failure
Engine at normal operating temperature; drive > 13 mph (20 km/h); engine speed > 1500 rpm; > 1 minute
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits A bank downstream O2S control
O2S disconnected
O2S mechanical damage
O2S to ECM wiring open circuit
O2S sensing circuit short circuit to high voltage
O2S short circuit to ground
O2S ground (BRD - braided shield) open circuit
Exhaust leak
Low exhaust temperature
O2S failure
Engine at normal operating temperature; drive at steady speed > 40 mph (60 km/h); engine speed 1300 - 4500 rpm > 1 minute 20 seconds
Y
2
N
None
HO2S disconnected
HO2S to ECM wiring open circuit
HO2S short circuit to ground
HO2S failure
Engine at normal operating temperature; drive at steady speed > 3 mph (4 km/h)
Y
2
N
None
HO2S sensing circuit short circuit to high voltage
HO2S ground (BRD - braided shield) open circuit
HO2S failure
Engine at normal operating temperature; drive at 50 - 62 mph (80 - 100 km/h); engine speed 1500 - 2500 rpm >10 seconds
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits B bank closed loop fuel metering
- Inhibits B bank adaptive fuel metering
Engine misfire
HO2S disconnected
HO2S mechanical damage
HO2S to ECM wiring intermittent open circuit
HO2S sensing circuit short circuit to high voltage
HO2S short circuit to ground
HO2S ground (BRD - braided shield) open circuit
HO2S heater circuit fault
Exhaust leak
Low exhaust temperature
Injector flow partially blocked
Catalyst efficiency decrease
HO2S failure
Engine at normal operating temperature; drive at steady speed > 20 mph (30 km/h)
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits B bank closed loop fuel metering
- Inhibits B bank adaptive fuel metering
- Inhibits B bank downstream O2S control
HO2S disconnected
HO2S heater power supply open circuit
HO2S heater to ECM wiring short circuit or open circuit
HO2S heater failure
Ambient temperature < 70 °C (158 °F); engine at normal operating temperature; drive at steady speed > 13 mph (20 km/h) > 1 minute 10 seconds
Y
2
N
None
O2S disconnected
O2S to ECM wiring open circuit
O2S short circuit to ground
Ambient temperature < 70 °C (158 °F); engine at normal operating temperature; drive at steady speed > 13 mph (20 km/h) > 1 minute 10 seconds
Y
2
N
None
O2S sensing circuit short circuit to high voltage
O2S ground (BRD - braided shield) open circuit
O2S failure
Engine at normal operating temperature; drive > 13 mph (20 km/h); engine speed > 1500 rpm; > 1 minute
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits B bank downstream O2S control
O2S disconnected
O2S mechanical damage
O2S to ECM wiring open circuit
O2S sensing circuit short circuit to high voltage
O2S short circuit to ground
O2S ground (BRD - braided shield) open circuit Exhaust leak
Low exhaust temperature
O2S failure
Engine at normal operating temperature; drive at steady speed > 40 mph; engine speed 1300 - 4500 rpm > 1 minute 20 seconds
Y
2
2 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits downstream O2S control If DTC P0174 is also flagged, ECM
- Limits engine speed to 3000 rpm
- Inhibits canister purge*
- Inhibits EGR
* Inhibited when "lean" fault is first detected
Engine misfire
Air intake leak between MAFS and throttle
Fuel filter, system blockage
Fuel injector blockage
Fuel pressure regulator failure (low fuel pressure)
Low fuel pump output
HO2S harness wiring condition fault
Exhaust leak (before catalyst)
ECM receiving incorrect signal from one or more of the following components: ECTS, MAFS, IATS, TPS
Engine at normal operating temperature; drive at steady speed > 40 mph; engine speed 1300 - 4500 rpm > 1 minute 20 seconds
Y
2
2 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits downstream O2S control If DTC P0175 is also flagged, ECM
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR
Blocked air filter
Fuel system return blockage
Leaking fuel injector(s)
Fuel pressure regulator failure (high fuel pressure) ECM receiving incorrect signal from one or more of the following components: ECTS, MAFS, IATS, TPS
Engine at normal operating temperature; drive at steady speed > 40 mph; engine speed 1300 - 4500 rpm > 1 minute 20 seconds
Y
2
2 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits downstream O2S control If DTC P0171 is also flagged, ECM
- Limits engine speed to 3000 rpm
- Inhibits canister purge*
- Inhibits EGR
* Inhibited when "lean" fault is first detected
Engine misfire
Air intake leak between MAFS and throttle
Fuel filter, system blockage
Fuel injector blockage
Fuel pressure regulator failure (low fuel pressure)
Low fuel pump output
HO2S harness wiring condition fault
Exhaust leak (before catalyst)
ECM receiving incorrect signal from one or more of the following components: ECTS, MAFS, IATS, TPS
Engine at normal operating temperature; drive at steady speed > 40 mph; engine speed 1300 - 4500 rpm > 1 minute 20 seconds
Y
2
2 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits downstream O2S control If DTC P0172 is also flagged, ECM
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR
Blocked air filter
Fuel system return blockage
Leaking fuel injector(s)
Fuel pressure regulator failure (high fuel pressure) ECM receiving incorrect signal from one or more of the following components: ECTS, MAFS, IATS, TPS
Engine at normal operating temperature; run engine > 30 seconds; engine speed 500 - 2500 rpm
Y
2
1 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR If DTCs for all A bank injectors are flagged
- Inhibits A bank closed loop fuel metering
- Inhibits A bank adaptive fuel metering
- Inhibits A bank downstream O2S control
Injector disconnected
Injector harness wiring open or short circuit
Injector failure
Engine at normal operating temperature; run engine > 30 seconds; engine speed 500 - 2500 rpm
Y
2
1 [A, M]
Refer to P0201 Default Action
Injector disconnected
Injector harness wiring open or short circuit
Injector failure
Engine at normal operating temperature; run engine > 30 seconds; engine speed 500 - 2500 rpm
Y
2
1 [A, M]
Refer to P0201 Default Action
Injector disconnected
Injector harness wiring open or short circuit
Injector failure
Engine at normal operating temperature; run engine > 30 seconds; engine speed 500 - 2500 rpm
Y
2
1 [A, M]
Refer to P0201 Default Action
Injector disconnected
Injector harness wiring open or short circuit
Injector failure
Engine at normal operating temperature; run engine > 30 seconds; engine speed 500 - 2500 rpm
Y
2
1 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR If DTCs for all B bank injectors are flagged
- Inhibits B bank closed loop fuel metering
- Inhibits B bank adaptive fuel metering
- Inhibits B bank downstream O2S control
Injector disconnected
Injector harness wiring open or short circuit
Injector failure
Engine at normal operating temperature; run engine > 30 seconds; engine speed 500 - 2500 rpm
Y
2
1 [A, M]
Refer to P0205 Default Action
Injector disconnected
Injector harness wiring open or short circuit
Injector failure
Engine at normal operating temperature; run engine > 30 seconds; engine speed 500 - 2500 rpm
Y
2
1 [A, M]
Refer to P0205 Default Action
Injector disconnected
Injector harness wiring open or short circuit
Injector failure
Engine at normal operating temperature; run engine > 30 seconds; engine speed 500 - 2500 rpm
Y
2
1 [A, M]
Refer to P0205 Default Action
Injector disconnected
Injector harness wiring open or short circuit
Injector failure
Ignition ON > 5 seconds
Y
2
1 [R, M]
When RED MIL is activated (DTC logged; first trip), ECM
- Defaults throttle to mechanical guard mode
- Inhibits idle speed control
- Inhibits cruise control
- Inhibits traction control/stability control
- Inhibits power limiting
TPS to ECM sensing circuit "2" (TPS pin 2) open circuit or high resistance
TPS failure
Ignition ON > 5 seconds
Y
2
1 [R, M]
Refer to P0222 Default Action
TPS to ECM sensing circuit "2" (TPS pin 2) short circuit to high voltage
TPS failure
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1 or 2 **
1 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Limits engine speed to 3000 rpm
- Inhibits closed loop fuel metering
- Inhibits adaptive fuel metering
- Inhibits canister purge
- Inhibits EGR
Cylinder compression low
Worn camshaft/broken valve spring(s)
Fuel delivery pressure (low/high)
Fuel injector(s) blocked/leaking
Fuel injector(s) continuously open
Fuel contamination
Fuel injector circuit fault(s) (Injector DTCs also flagged)
Spark plug failure/fouled/incorrect gap
ECM to ignition module primary circuit fault(s) (Cylinder misfire detected DTC also flagged)
Ignition module to ignition coil primary circuit fault(s) (Cylinder misfire detected DTC also flagged) Ignition module ground circuit open circuit, high resistance
Ignition coil failure
Ignition module failure
** If, on the first trip, the misfire is severe enough to cause excess exhaust emission, individual cylinder DTC plus DTC P1316 will be flagged; CHECK ENGINE MIL will flash.
If, on the first trip, the misfire is severe enough to cause catalyst damage, individual cylinder DTC plus DTC P1313 (A bank) or P1314 (B bank) will be flagged; CHECK ENGINE MIL will flash.
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1 or 2 **
1 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Limits engine speed to 3000 rpm
- Inhibits A bank closed loop fuel metering
- Inhibits A bank adaptive fuel metering
- Inhibits canister purge
- Inhibits EGR
Refer to P0300 Possible Faults
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1 or 2 **
1 [A, M]
Refer to P0301 Default Action
Refer to P0300 Possible Faults
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1 or 2 **
1 [A, M]
Refer to P0301 Default Action
Refer to P0300 Possible Faults
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1 or 2 **
1 [A, M]
Refer to P0301 Default Action
Refer to P0300 Possible Faults
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1 or 2 **
1 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Limits engine speed to 3000 rpm
- Inhibits B bank closed loop fuel metering
- Inhibits B bank adaptive fuel metering
- Inhibits canister purge
- Inhibits EGR
Refer to P0300 Possible Faults
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1 or 2 **
1 [A, M]
Refer to P0305 Default Action
Refer to P0300 Possible Faults
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1 or 2 **
1 [A, M]
Refer to P0305 Default Action
Refer to P0300 Possible Faults
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1 or 2 **
1 [A, M]
Refer to P0305 Default Action
Refer to P0300 Possible Faults
** If, on the first trip, the misfire is severe enough to cause excess exhaust emission, individual cylinder DTC plus DTC P1316 will be flagged; CHECK ENGINE MIL will flash.
If, on the first trip, the misfire is severe enough to cause catalyst damage, individual cylinder DTC plus DTC P1313 (A bank) or P1314 (B bank) will be flagged; CHECK ENGINE MIL will flash.
Ignition ON > 5 seconds
Y
2
N
When DTC is logged (first trip), ECM
- Sets ignition retard to maximum
Poor sensor contact with the cylinder block KS to ECM sense circuit short circuit to ground KS failure
Ignition ON > 5 seconds
Y
2
N
When DTC is logged (first trip), ECM
- Sets ignition retard to maximum
Poor sensor contact with the cylinder block KS to ECM sense circuit high resistance or open circuit
KS to ECM sense circuit short circuit to high voltage
KS failure
Ignition ON > 5 seconds
Y
2
N
When DTC is logged (first trip), ECM
- Sets ignition retard to maximum
Poor sensor contact with the cylinder block KS to ECM sense circuit short circuit to ground
KS failure
Ignition ON > 5 seconds
Y
2
N
When DTC is logged (first trip), ECM
- Sets ignition retard to maximum
Poor sensor contact with the cylinder block KS to ECM sense circuit high resistance or open circuit
KS to ECM sense circuit short circuit to high voltage
KS failure
Crank engine > 5 seconds - engine will not start; or start engine, run steady > 1000 rpm; or engine stall, ignition ON
Y
2
N
None
CKPS disconnected
CKPS gap incorrect/foreign matter on sensor face CKPS sensing circuit open circuit, short circuit to ground, short circuit to high voltage
CKPS failure
Crank engine > 5 seconds
Y
2
N
When fault is detected, ECM
- Guesses camshaft position (engine starts 50% of time - rough running)
CMPS disconnected
CMPS gap incorrect/foreign matter on sensor face CMPS sensing circuit open circuit, short circuit to ground, short circuit to high voltage
CMPS failure
Run engine steady < 3000 rpm > 5 seconds
Y
2
1 [A, M]
When fault is detected, ECM
- Inhibits individual cylinder fuel injection
- Inhibits A bank closed loop fuel metering
- Inhibits A bank downstream O2S control
ECM to ignition module primary circuit open circuit, short circuit to ground, high resistance
Ignition module to ignition coil primary circuit open circuit, short circuit to ground, high resistance
Ignition module ground circuit open circuit, high resistance
Ignition coil failure
Ignition module failure
Run engine steady < 3000 rpm > 5 seconds
Y
2
1 [A, M]
Refer to P0351 Default Action
Refer to P0351 Possible Causes
Run engine steady < 3000 rpm > 5 seconds
Y
2
1 [A, M]
Refer to P0351 Default Action
Refer to P0351 Possible Causes
Run engine steady < 3000 rpm > 5 seconds
Y
2
1 [A, M]
Refer to P0351 Default Action
Refer to P0351 Possible Causes
Run engine steady < 3000 rpm > 5 seconds
Y
2
1 [A, M]
When fault is detected, ECM
- Inhibits individual cylinder fuel injection
- Inhibits B bank closed loop fuel metering
- Inhibits B bank downstream O2S control
Refer to P0351 Possible Causes
Run engine steady < 3000 rpm > 5 seconds
Y
2
1 [A, M]
Refer to P0355 Default Action
Refer to P0351 Possible Causes
Run engine steady < 3000 rpm > 5 seconds
Y
2
1 [A, M]
Refer to P0355 Default Action
Refer to P0351 Possible Causes
Run engine steady < 3000 rpm > 5 seconds
Y
2
1 [A, M]
Refer to P0355 Default Action
Refer to P0351 Possible Causes
Engine at normal operating temperature; normal, varied driving for 3 minutes; then decel./accel. 50 - 60 mph (80 - 95 km/h), within 6 seconds between 1700 - 2050 rpm
Y
2
N
None
EGR valve connector pins high resistance
EGR pipe/exhaust manifold leak
EGR pipe blocked
EGR valve stuck open/closed, blocked
EGR valve failure
Ignition ON > 5 seconds
Y
2
N
None
EGR valve power supply circuit open circuit
EGR valve to ECM drive circuit pair - EGR pins 1/3, 4/6 open circuit, high resistance
EGR valve failure (stepper motor open circuit)
Ignition ON > 5 seconds
Y
2
N
When fault is detected, ECM
- Inhibits EGR
EGR valve to ECM drive circuit pair - EGR pins 1/3, 4/6 short circuit to ground or high voltage
EGR valve failure (stepper motor short circuit)
Y
2
N
None
HO2S/O2S disconnected
HO2S/O2S to ECM wiring fault
HO2S heater to ECM wiring fault
HO2S heater failure Upstream
HO2S failure Downstream
O2S failure Catalyst failure
Ambient (IATS) temperature > 20 °C (68 °F); engine at normal operating temperature; normal, varied driving for 3 minutes; then, constant steady throttle 50 - 60 mph (80 - 95 km/h), 1500 - 2300 rpm > 15 seconds; then, constant steady throttle 30 - 38 mph (50 - 60 km/h), 1100 - 1900 rpm > 15 seconds
Y
2
N
None
HO2S/O2S disconnected
HO2S/O2S to ECM wiring fault
HO2S heater to ECM wiring fault
HO2S heater failure Upstream
HO2S failure Downstream
O2S failure Catalyst failure
Engine at normal operating temperature; vehicle stationary; brakes applied; gear "D"; idle > 10 minutes (from engine start); fuel tank > 1/4 full
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits adaptive fuel metering
- Inhibits canister purge
EVAPP to ECM drive circuit open circuit, short circuit, high resistance
EVAPP power supply circuit open circuit
EVAPP to engine purge pipe damaged/blocked/leaking
EVAPP operating vacuum hose leak/blockage
EVAPP failure
Engine at normal operating temperature; vehicle stationary; brakes applied; gear "D"; idle > 10 seconds
Y
2
N
Refer to P0441 Default Action
EVAPP to ECM drive circuit open circuit or high resistance
EVAPP failure
Engine at normal operating temperature; vehicle stationary; brakes applied; gear "D"; idle > 10 seconds
Y
2
N
Refer to P0441 Default Action
EVAPP to ECM drive circuit short circuit to ground
EVAPP failure
Drive > 30 miles (48 km)
Y
2
N
None
Fuel level sensor to instrument pack circuits intermittent short or open circuit, high resistance
Fuel level sensor failure
Instrument pack fault (incorrect fuel level data)
Engine at normal operating temperature; transmission at normal operating temperature; gear "N"; idle > 1 minute 40 seconds (no electrical load, A/C compressor, radiator fans, brake pedal switching during period)
Y
2
N
None
Air intake blockage
Accessory drive overload (defective/seized component)
Throttle valve stuck closed
Throttle assembly failure
Engine at normal operating temperature; transmission at normal operating temperature; gear "N"; idle > 1 minute 40 seconds (no electrical load, A/C compressor, radiator fans, brake pedal switching during period)
Y
2
N
None
Intake air leak between MAFS and throttle
Intake air leak between throttle and engine
Engine breather leak
Cruise control vacuum failure
Throttle valve stuck open
Throttle assembly failure
Ignition ON > 35 seconds
Y
2
N
None
ECM battery power supply open circuit, high resistance
ECM ignition power supply open circuit, high resistance
Ignition ON > 75 seconds
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
Cruise control switches internal steering wheel short circuit to ground
Steering wheel cassette reel short circuit to ground
Cassette reel to ECM circuit short circuit to ground
CANCEL switch failure (stuck ON)
Ignition ON > 75 seconds
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
Cruise control switches internal steering wheel short circuit to ground
Steering wheel cassette reel short circuit to ground
Cassette reel to ECM circuit short circuit to ground RESUME switch failure (stuck ON)
Ignition ON > 5 seconds
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
Cruise control switches internal steering wheel open circuit
Steering wheel cassette reel open circuit or high resistance
Cassette reel to ECM circuit (ACCEL/DECEL) open circuit or high resistance ACCEL/DECEL switch failure
Ignition ON > 10 minutes
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
Cruise control switches internal steering wheel short circuit to ground
Steering wheel cassette reel short circuit to ground
Cassette reel to ECM circuit short circuit to ground DECEL/set switch failure (stuck ON)
Ignition ON > 10 minutes
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
Cruise control switches internal steering wheel short circuit to ground
Steering wheel cassette reel short circuit to ground
Cassette reel to ECM circuit short circuit to ground ACCEL/set failure (stuck ON)
Ignition ON > 5 seconds
Y
1
N
None
ECM failure
"System Readiness Test"
N
N
N
None
See OBD II MONITORING CONDITIONS
Ignition ON > 5 seconds
Y
2
1 [A, M]
When AMBER MIL is activated (DTC logged; first trip), ECM
- Substitutes throttle angle for engine load measurement
- Limits engine speed to 3000 rpm
- Inhibits canister purge
- Inhibits EGR
MAFS to ECM reference ground circuit open circuit, short circuit to high voltage, high resistance
MAFS to ECM sensing circuit open circuit
MAFS failure
"System Readiness Test"
N
N
N
None
See OBD II MONITORING CONDITIONS
Ignition ON > 5 seconds
N
N
1 [A, M]
None
Pedal position sensor to ECM sense circuit "A" (sensor pin 5) open circuit, short circuit or high resistance Sensor power supply fault
Sensor reference ground fault
Pedal position sensor failure
Ignition ON > 5 seconds
N
N
1 [A, M]
None
Pedal position sensor to ECM sense circuit "A" (sensor pin 5) wire open circuit or high resistance
Sensor power supply fault
Pedal position sensor failure
Ignition ON > 5 seconds
N
N
1 [A, M]
None
Pedal position sensor to ECM sense circuit "A" (sensor pin 5) wire short circuit to high voltage
Pedal position sensor failure
Ignition ON > 5 seconds
N
N
1 [A, M]
None
Pedal position sensor to ECM sense circuit "B" (sensor pin 3) open circuit, short circuit or high resistance Sensor power supply fault Sensor reference ground fault
Pedal position sensor failure
Ignition ON > 5 seconds
N
N
1 [A, M]
None
Pedal position sensor to ECM sense circuit "B" (sensor pin 3) wire open circuit or high resistance Sensor power supply fault
Pedal position sensor failure
Ignition ON > 5 seconds
N
N
1 [A, M]
None
Pedal position sensor to ECM sense circuit "B" (sensor pin 3) wire short circuit to high voltage
Pedal position sensor failure
Ignition ON > 3 minutes
Y
2
1 [R, M]
When RED MIL is activated (DTC logged; first trip), ECM
- Defaults throttle to mechanical guard mode
- Inhibits idle speed control
- Inhibits cruise control
- Inhibits traction control/stability control
- Inhibits power limiting
Throttle adaptions not performed after battery disconnect
TPS disconnected
TPS to ECM sense circuits open circuit, high resistance
Throttle motor power relay failure
Throttle motor power relay to ECM circuit fault
Throttle motor power relay power supply open circuit
ECM ground circuit fault (relay coil drive)
Throttle motor to ECM drive circuits open circuit, short circuit, high resistance
Throttle motor failure
Throttle assembly failure
Ignition ON > 5 seconds
Y
2
1 [A, M]
When AMBER MIL is activated (DTC logged; first trip), ECM
- Inhibits cruise control
Mechanical guard sensor to ECM sense circuit open circuit, short circuit or high resistance
Sensor power supply fault
Sensor reference ground fault
Mechanical guard sensor failure
Mechanical guard actuator seized/spring broken
Ignition ON > 5 seconds
Y
2
1 [A, M]
When AMBER MIL is activated (DTC logged; first trip), ECM
- Inhibits cruise control
Mechanical guard sensor to ECM sense circuit open circuit or high resistance
Sensor power supply fault
Mechanical guard sensor failure
Ignition ON > 5 seconds
Y
2
1 [A, M]
When AMBER MIL is activated (DTC logged; first trip), ECM
- Inhibits cruise control
Mechanical guard sensor to ECM sense circuit short circuit to high voltage
Mechanical guard sensor failure
Ignition ON > 5 seconds
Y
2
1 [R, M]
When RED MIL is activated (DTC logged; first trip), ECM
- Defaults throttle to mechanical guard mode
- Inhibits idle speed control
- Inhibits cruise control
- Inhibits traction control/stability control
- Inhibits power limiting
Throttle motor disconnected
Throttle motor to ECM drive circuits short circuit or open circuit
Throttle motor failure
Ignition ON > 5 seconds
Y
2
N
None
Fuel pump relay failure
Fuel pump relay to ECM circuit fault
Fuel pump relay coil power supply open circuit
ECM ground circuit fault (relay coil drive)
Drive with cruise control engaged > 15 seconds
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
Vacuum leak/blockage between the throttle elbow and the throttle vacuum actuator
Vacuum actuator failure
Mechanical guard actuator seized/spring broken
Ignition ON > 5 seconds
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
VSV 1 disconnected
VSV 1 to ECM drive circuit high resistance, open circuit or short circuit
VSV 1 power supply open circuit
VSV 1 failure
Ignition ON > 5 seconds
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
VSV 2 disconnected
VSV 2 to ECM drive circuit high resistance, open circuit or short circuit
VSV 2 power supply open circuit
VSV 2 failure
Ignition ON > 5 seconds
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
VSV 3 disconnected
VSV 3 to ECM drive circuit high resistance, open circuit or short circuit
VSV 3 ground circuit fault
VSV 3 failure
Ignition ON > 5 seconds
Y
2
1 [R, M]
When RED MIL is activated (DTC logged; first trip), ECM
- Defaults throttle to mechanical guard mode
- Inhibits idle speed control
- Inhibits cruise control
- Inhibits traction control/stability control
- Inhibits power limiting
ECM to throttle sensors reference voltage circuit short circuit to ground, short circuit to high voltage, open circuit, high resistance
TPS, pedal position and mechanical guard sensor(s) failure(s)
Ignition ON > 5 seconds
Y
2
1 [R, M]
Refer to P1240 Default Action
ECM to throttle sensors reference voltage circuit short circuit to ground
TPS, pedal position and mechanical guard sensor(s) failure(s)
Ignition ON > 5 seconds
Y
2
1 [R, M]
Refer to P1240 Default Action
ECM to throttle sensors reference voltage circuit open circuit, high resistance, short circuit to high voltage
TPS, pedal position and mechanical guard sensor(s) failure(s)
Ignition ON > 5 seconds
Y
2
1 [R, M]
Refer to P1240 Default Action
ECM to sensors reference ground circuit open circuit, high resistance
Throttle sensor(s), ECTS, IATS failure(s)
Start engine; idle
Y
2
N
None
Starter relay coil to ECM/BPM circuit open circuit
Start engine; drive/accelerate > 13 mph (20 km/h) 1200 - 3000 rpm decelerate to stop; repeat (5 times total)
Y
2
N
None
Starter relay coil to ECM/BPM circuit short circuit to B+ voltage
BPM failure
Engine at normal operating temperature; drive vehicle; accelerate from 3500 to 6000 rpm within 6 seconds; drive 43 - 59 mph (70 - 95 km/h); 1500 - 2500 rpm; > 10 seconds
N
N
N
None
Air intake leak
Engine breather leak
TPS circuit fault (DTC P0121)
Throttle valve spring failure
Drive vehicle; decelerate to stop, ignition OFF > 5 seconds (foot off accelerator); ignition ON
N
N
N
None
TPS to ECM wiring open circuit or high resistance
TPS to ECM sensing circuits ("1" or "2") short circuit to high voltage
TPS failure
Throttle motor disconnected
Throttle motor to ECM drive circuits short circuit or open circuit
Throttle motor failure
Throttle assembly failure
Drive vehicle; engage cruise control > 5 seconds
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
VSV 1,2,3 vacuum and/or electrical circuit fault(s) open circuit, short circuit or high resistance
Mechanical guard sensor to ECM sense circuit
Mechanical guard sensor failure
Mechanical guard actuator seized/spring broken Throttle vacuum actuator fault
Engine at normal operating temperature; drive/accelerate from 3500 to 6000 rpm within 6 seconds; decelerate to stop, ignition OFF > 5 seconds (foot off accelerator); ignition ON
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
VSV 1,2,3 vacuum and/or electrical circuit fault(s)
Mechanical guard sensor to ECM sense circuit open circuit, short circuit or high resistance
Mechanical guard sensor failure
Mechanical guard actuator seized/spring broken Throttle vacuum actuator fault
Ignition ON > 10 seconds
N
N
N
None
KTM to ECM circuit short circuit, high resistance or open circuit
KTM failure
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1
1 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Limits engine speed to 3000 rpm
- Inhibits A bank closed loop fuel metering
- Inhibits A bank adaptive fuel metering
- Inhibits canister purge
- Inhibits EGR
Cylinder compression low
Worn camshaft/broken valve spring(s)
Fuel delivery pressure (low/high)
Fuel injector(s) blocked/leaking
Fuel injector(s) continuously open
Fuel contamination
Fuel injector circuit fault(s) (Injector DTCs also flagged)
Spark plug failure/fouled/incorrect gap
ECM to ignition module primary circuit fault(s) (Cylinder misfire detected DTC also flagged)
Ignition module to ignition coil primary circuit fault(s) (Cylinder misfire detected DTC also flagged)
Ignition module ground circuit open circuit, high resistance
Ignition coil failure Ignition module failure
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1
1 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Limits engine speed to 3000 rpm
- Inhibits B bank closed loop fuel metering
- Inhibits B bank adaptive fuel metering
- Inhibits canister purge
- Inhibits EGR
Refer to P1313 Possible Causes
Engine at idle, or steady between 500 - 2500 rpm; > 2 minutes 30 seconds
Y
1
1 [A, M]
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Limits engine speed to 3000 rpm
- Inhibits closed loop fuel metering
- Inhibits adaptive fuel metering
- Inhibits canister purge
- Inhibits EGR
Refer to P1313 Possible Causes
Run engine > 5 seconds
Y
2
N
None
CKPS/CMPS disconnected
CKPS/CMPS gap incorrect/foreign matter on sensor face
CKPS/CMPS sensing circuit open circuit, short circuit to ground, short circuit to high voltage
CKPS/CMPS failure
Run engine > 5 seconds < 3000 rpm
Y
2
1 [A, M]
When fault is detected, ECM
- Limits engine speed to 3000 rpm
Ignition module 1 disconnected
Ignition module 1 to ECM circuits open circuit, short circuit to ground or short circuit to B+ voltage
Ignition module 1 ground circuit fault
Ignition coil relay failure
Ignition coil open/short circuit
Ignition module 1 failure
Run engine > 5 seconds < 3000 rpm
Y
2
1 [A, M]
When fault is detected, ECM
- Limits engine speed to 3000 rpm
Ignition module 2 disconnected
Ignition module 2 to ECM circuits open circuit, short circuit to ground or short circuit to B+ voltage
Ignition module 2 ground circuit fault
Ignition coil relay failure
Ignition coil open/short circuit
Ignition module 2 failure
Ignition ON > 5 seconds
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits VVT
ECM to VVT solenoid valve circuit open circuit, high resistance, short circuit to high voltage
VVT solenoid valve failure
Ignition ON > 5 seconds
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits VVT
ECM to VVT solenoid valve short circuit to ground VVT solenoid valve failure
Engine at normal operating temperature; drive > 13 mph (20 km/h) > 1700 rpm > 5 seconds
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits VVT
ECM to VVT solenoid valve circuit fault (refer to P1392 , P1393 )
VVT solenoid valve actuator sticking
Oil supply fault
VVT unit fault
Camshaft drive fault
CKPS/CMPS circuits fault(s) (refer to P0335 , P0340 )
Ignition ON > 5 seconds
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits VVT
ECM to VVT solenoid valve open circuit, high resistance, short circuit to high voltage
VVT solenoid valve failure
Ignition ON > 5 seconds
Y
2
N
When CK ENG MIL is activated (DTC flagged; second trip), ECM
- Inhibits VVT
ECM to VVT solenoid valve short circuit to ground
VVT solenoid valve failure
Engine at normal operating temperature; fans cycle ON/OFF
N
N
N
None
Radiator fan control relay module to ECM "series" drive circuit (relay pin 9) fault
Relay coil ignition power supply open circuit
ECM ground circuit fault (relay coil drive)
ECTS circuit malfunction (refer to P0116 )
Engine at normal operating temperature; fans cycle ON/OFF
N
N
N
None
Radiator fan control relay module to ECM "parallel" drive circuit (relay pin 7) fault
Relay coil ignition power supply open circuit
ECM ground circuit fault (relay coil drive)
ECTS circuit malfunction (refer to P0116 )
Engine at normal operating temperature; drive 50 - 63 mph (80 - 100 km/h) 1800 - 2200 rpm > 30 seconds
Y
2
N
None
Transmission rotary switch to ECM circuit open circuit or high resistance
Rotary switch failure
D - 4 switch to TCM circuit open circuit or high resistance
D - 4 switch fault
Start engine
N
CK ENG
N*
N
When fault is detected, ECM
- Inhibits fuel injection
Transmission rotary switch to ECM circuit open circuit or high resistance
Rotary switch failure
* If engine will not start, CHECK ENGINE MIL will remain on.
Drive vehicle; engage cruise control > 10 seconds disengage cruise control; repeat (5 total cycles)
N
N
1 [A, M]
When fault is detected, ECM
- Inhibits cruise control
Brake switch to ECM circuit open circuit, short circuit to ground, high resistance
Brake switch ignition switched ground circuit open circuit Brake switch failure
Brake cancel switch to ECM circuit open circuit, short circuit to ground, high resistance
Brake cancel switch to cruise control switch to ECM circuit open circuit, short circuit to ground, high resistance
Brake cancel switch ignition switched power supply open circuit
Brake cancel switch failure Cruise control switch failure
Ignition ON; ignition OFF; ignition ON > 5 seconds
N
N
None
None
ECM control relay failure
ECM control relay to ECM circuit fault
ECM control relay coil power supply open circuit
ECM ground circuit fault (relay coil drive)
Ignition ON > 5 seconds
Y
2
N
None
ECM FCCP (programming) circuit (ECM pin EM11-3) short circuit to ground
ECM failure
Ignition ON > 5 seconds
Y
2
1 [R, M]
When RED MIL is activated (first trip), ECM
- Defaults throttle to mechanical guard mode
- Inhibits idle speed control
- Inhibits cruise control
- Inhibits traction/stability control
- Inhibits power limiting
TPS circuit fault (refer to P0121 ) Pedal position sensor circuit fault (refer to P01121) Throttle assembly failure
ECM failure
Ignition ON > 5 seconds
Y
2
1 [R, M]
Refer to P1611 Default Action
TPS circuit fault (refer to P0121 ) Pedal position sensor circuit fault (refer to P01121) Throttle assembly failure
ECM failure
Ignition ON > 5 seconds
Y
2
N
When fault is detected, ECM
- Inhibits cruise control (Idle speed control quality deteriorates)
CAN open circuit fault - ABS/TCCM to ECM CAN short circuit fault ABS/TCCM failure
ECM failure
Ignition ON > 5 seconds
Y
1
N
None
(Engine speed and coolant temperature data missing at instrument pack)
CAN open circuit fault - INST to ECM
CAN short circuit fault
INST failure
ECM failure
Ignition ON > 5 seconds
Y
1
N
When fault is detected, ECM
- Inhibits cruise control (All CAN data unavailable)
CAN short circuit fault
Control module failure - check for additional flagged DTC(s) to locate control module source
Ignition ON > 5 seconds
Y
2
N
When fault is detected, ECM
- Limits throttle to 30% (Torque reduction request data missing results in harsh transmission shifts)
CAN open circuit fault - TCM to ECM CAN short circuit fault
TCM failure
ECM failure