Vin SUZUKI SWIFT 2006 2.G Service Owner's Manual

Downloaded from www.Manualslib.com manuals search engine 1A-30 Engine General Information and Diagnosis:
)
U *P0617 Starter relay circuit high Starter signal is high voltage for specified time while
engine is running. 2 driving
cycles
) P0620 Generator control circuit Battery voltage is higher than specification even through
generator control is maximum regulation, or battery
voltage is lower than specification even through generator
control is minimum regulation
and electric load is less
than 15 A. —
) P0625 Generator field/F terminal
circuit low Generator field coil duty is
0% (high voltage) for more
than specified time even through generator control is
minimum regulation. —
) P0626 Generator field/F terminal
circuit high Generator field coil duty is
100% (low voltage) for more
than specified time even through generator control is
maximum regulation, or generator field coil duty is 100%
(low voltage) when engine is starting. —
) P1501 Electric load current sensor
circuit low Electric load current is lowe
r than specified value (electric
load current sensor voltage is higher than specified
value). —
) P1502 Electric load current sensor
circuit high Electric load current is higher than specified value
(electric load current sens
or voltage is lower than
specified value). —
)
U *P1510 ECM backup power supply
malfunction Backup power voltage is out of
specification after starting
engine. 1 driving
cycle
) † P1603 TCM trouble code detected When ECM receives a trouble code from TCM, which
indicates that some problem occurred in sensor circuits
and its calculated values used for operations such as idle
speed control, engine power control and so on by TCM,
this DTC is detected by ECM. —
) *P1674 CAN communication (buss off
error) Transmission error that
is inconsistent between
transmission data and transmission monitor (CAN bus
monitor) data is detected more than 7 times continuously. 1 driving
cycle
)
† *P1676 CAN communication (reception
error for TCM) Reception error of communication data for TCM is
detected for longer than specified time continuously. 1 driving
cycle
) P1678 CAN communication (reception
error for BCM) Reception error of communication data for BCM is
detected for longer than specified time continuously.
—
) *P1685 CAN communication (reception
error for ABS/ESP
® control
module) Reception error of communication data for ABS/ESP
®
co

ntrol module is detected for longer than specified time
continuously. 1 driving
cycle
) *P2101 Throttle actuator control motor
circuit range/performance Monitor signal of throttle actuator output (duty output) is
inconsistent with throttle actuator control command. 1 driving
cycle
) *P2102 Throttle actuator control motor
circuit low Power supply voltage of throttle actuator control circuit is
lower than specification even
if throttle actuator control
relay turned on. 1 driving
cycle
) *P2103 Throttle actuator control motor
circuit high Power supply voltage of throttle actuator control circuit is
higher than specification even if throttle actuator control
relay turned off. 1 driving
cycle
) *P2111 Throttle actuator control
system – stuck open Throttle valve default opening is greater than specified
value from complementary closed position when
diagnosing throttle valve at ignition switch turned OFF. 1 driving
cycle
) *P2112 Throttle actuator control
system – stuck closed Throttle valve default opening is smaller than specified
value from complementary closed position when
diagnosing throttle valve at ignition switch turned OFF. 1 driving
cycle
) *P2119 Throttle actuator control throttle
body range/performance Difference between actual throttle valve opening angle
and opening angle calculated by ECM is more than
specification. 1 driving
cycle
) *P2122 Throttle/pedal position sensor/
switch “D” (main) circuit low
input Output voltage of APP sensor (main) is lower than
specification.
1 driving
cycle
DTC No. Detecting item
Detecting condition
(DTC will set when detecting:) MIL

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-31
Fail-Safe TableS7RS0B1104006
When any of the following DTCs is detected, ECM enters fail-safe mode as long as malfunction continues to exist but
that mode is canceled when ECM de tects normal condition after that.
)
*P2123 Throttle/pedal position sensor/
switch “D” (main) circuit high
input Output voltage of APP sensor (main) is higher than
specification.
1 driving
cycle
) *P2127 Throttle/pedal position sensor/
switch “E” (sub) circuit low
input Output voltage of APP sens
or (sub) is lower than
specification. 1 driving
cycle
) *P2128 Throttle/pedal position sensor/
switch “E” (sub) circuit high
input Output voltage of APP sensor (sub) is higher than
specification.
1 driving
cycle
) *P2135 Throttle/pedal position sensor/
switch “A”/“B” (main / sub)
voltage correlation Difference between the opening angle based on TP
sensor (main) and the opening angle based on TP sensor
(sub) is more than specification.
1 driving
cycle
) *P2138 Throttle/pedal position sensor/
switch “D”/“E” (main / sub)
voltage correlation Difference between the opening angle based on APP
sensor (main) and the opening angle based on APP
sensor (sub) is more
than specification. 1 driving
cycle
)
U *P2227 Barometric pressure circuit
range/performance Difference of barometric pressure value and intake
manifold pressure value is
more than specification at
engine start. 2 driving
cycles
) *P2228 Barometric pressure circuit low Barometric pressure sens
or voltage is less than
specification. 1 driving
cycle
) *P2229 Barometric pressure circuit
high Barometric pressure sensor voltage is more than
specification. 1 driving
cycle
) P1614 Transponder response error
Refer to “Diagnostic Trouble Code (DTC) Table in Section
10C”. —

) P1615 ID code does not registered
(vehicle equipped with keyless
start system only)
) P1616 Different registration ID codes
(vehicle equipped with keyless
start system only)
) P1618 CAN communication error
(reception error for keyless
start control module) (vehicle
equipped with keyless start
system only)
) P1621 Immobilizer communication
line error
) P1622
EEPROM error
) P1623 Unregistered transponder
) P1625 Immobilizer antenna error
) P1636 Immobilizer information
registration failure
) P1638 Immobilizer information
mismatched
DTC No. Detecting item
Detecting condition
(DTC will set when detecting:) MIL
DTC No.
Detected item Fail-safe operation
) P0031 HO2S heater control circuit low (Sensor-1)
ECM stops air/fuel ratio control.
) P0032 HO2S heater control circuit high (Sensor-1)
) P0102 Mass or volume air flow circuit low input • ECM controls injector drive time (fuel injection
volume) according to throttle valve opening
(closed throttle position or not).
• ECM stops EGR control.
)
P0103 Mass or volume air flow circuit high input
) P0112 Intake air temperature sensor 1 circuit low ECM controls actuators assuming that intake air
temperature is 20 °C (68 ° F).
) P0113 Intake air temperature sensor 1 circuit high

Downloaded from www.Manualslib.com manuals search engine 1A-36 Engine General Information and Diagnosis:
O2S B1 S1 ACT (HEATED OXYGEN SENSOR-1,
ACTIVE / INACTIVE)
This parameter indicates activation condition of HO2S-1.
ACTIVE: Activating
INACTIVE: warming up or at stop
O2S SENSOR B1 S2 (HEATED OXYGEN SENSOR-2,
V)
It indicates output voltage of HO2S-2 installed on
exhaust pipe (post-catalyst). It is used to detect catalyst
deterioration.
O2S B1 S2 ACT (HEATED OXYGEN SENSOR-2,
ACTIVE / INACTIVE)
This parameter indicates acti vation condition of HO2S-2.
ACTIVE: Activating
INACTIVE: warming up or at stop
FUEL SYSTEM (FUEL SYSTEM STATUS)
Air/fuel ratio feedback loop status displayed as one of
the followings.
OPEN: Open-loop has not yet satisfied conditions to go
closed loop.
CLOSED: Closed-loop using oxygen sensor(s) as
feedback for fuel control.
OPEN-DRIVE COND: Open-loop due to driving
conditions (Power enrichment, etc.).
OPEN SYS FAULT: Open-loop due to detected system
fault.
MAP (MANIFOLD ABSOLUTE PRESSURE, in.Hg,
kPa)
This value indicates how much correction is necessary
to keep the air/fuel mixture stoichiometrical.
It is detected by manifold absolute pressure sensor.
BAROMETRIC PRESS (kPa, in.Hg)
This parameter represents a measurement of barometric
air pressure and is used for al titude correction of the fuel
injection quantity and IAC valve control.
STEP EGR FLOW DUTY (%)
This parameter indicates opening rate of EGR valve
which controls the amount of EGR flow.
FUEL CUT (ON/OFF)
ON: Fuel being cut (output signal to injector is stopped)
OFF: Fuel not being cut
A/C PRESSURE (A/C REFRIGERANT ABSOLUTE
PRESSURE, kPa)
This parameter indicates A/C refrigerant absolute
pressure calculated by ECM.
CLOSED THROTTLE PO S (CLOSED THROTTLE
POSITION, ON/OFF)
This parameter reads ON wh en throttle valve is fully
closed, or OFF when it is not fully closed. CANIST PRG DUTY (EVAP CANISTER PURGE FLOW
DUTY, %)
This parameter indicates valve ON (valve open) time
rate within a certain set cycle of EVAP canister purge
valve which controls the amount of EVAP purge.
IGNITION ADVANCE (IGNITION TIMING ADVANCE
FOR NO.1 CYLINDER,
°)
Ignition timing of No.1 cylinder is commanded by ECM.
The actual ignition timing should be checked by using
the timing light.
BATTERY VOLTAGE (V)
This parameter indicates battery positive voltage
inputted from main relay to ECM.
FUEL PUMP (ON/OFF)
ON is displayed when ECM activates the fuel pump via
the fuel pump relay switch.
ELECTRIC LOAD (ON/OFF)
ON: Headlight or small light ON signal inputted.
OFF: Above electric loads all turned OFF.
BRAKE SW (ON/OFF)
This parameter indicates the state of the brake switch.
RADIATOR COOLING FAN (RADIATOR COOLING
FAN CONTROL RELAY, ON/OFF)
ON: Command for radiator cooling fan control relay
operation being output.
OFF: Command for relay operation not being output.
BLOWER FAN (ON/OFF)
This parameter indicates the state of the blower fan
motor switch.
A/C SWITCH (ON/OFF)
ON: Command for A/C operatio n being output from ECM
to HVAC.
OFF: Command for A/C oper ation not being output.
A/C COMP RELAY (A/C COMPRESSOR RELAY, ON/
OFF)
This parameter indicates the state of the A/C switch.
VEHICLE SPEED (km/h, mph)
It is computed based on pulse signals from vehicle
speed sensor.
VVT GAP (TARGET-ACTUAL POSITION, °)
It is calculated using the formula: target valve timing
advance – actual valve timing advance.
TP SENSOR 1 VOLT (THROTTLE POSITION SENSOR
(MAIN) OUTPUT VOLTAGE, V)
The TP sensor (main) reading provides throttle valve
opening information in the form of voltage.

Downloaded from www.Manualslib.com manuals search engine 1A-50 Engine General Information and Diagnosis:
Circuit Description
Actual valve timing fails to become close to target advance level of each function although advance control function or
retarded advance control function is at work.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure 1) Clear DTC. Refer to “DTC Clearance”.
2) Start engine and keep it at idle for 10 seconds.
3) Check DTC. Refer to “DTC Check”.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

DTC detecting condition Trouble area
Monitor signal of oil control valve is different from
command signal. (Circuit open or short)
(1 driving cycle detection logic) • Oil control valve
• Oil control valve circuit
•ECM
Step
Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 Oil control valve electrical circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Check for proper connection at “C37-60” and “C37-59” terminals of ECM connector.
3) If OK, measure resistance between “C37-60” and “C37- 59” terminals of ECM connector.
Is resistance below 10
Ω? Go to Step 3. Go to Step 8.
3 Oil control valve electrical circuit check
Was resistance more than 6.5
Ω in Step 2? Go to Step 4. Go to Step 7.
4 Oil control valve electrical circuit for power short check
1) Turn ON ignition switch.
2) Measure voltage between “C37-60” terminal of ECM
connector and engine ground.
Is voltage below 1 V? Go to Step 5. “RED”, “YEL/RED”,
“YEL” or “YEL/GRN”
wire is shorted to power
supply circuit.
5 Oil control valve electrical circuit for ground short
check
1) Disconnect connector from oil control valve with ignition
switch turned OFF.
2) Measure resistance between “C37-60” terminal of ECM connector and engine ground.
Is resistance infinity? Go to Step 6. “YEL/RED” wire is
shorted to ground
circuit.

Downloaded from www.Manualslib.com manuals search engine 1A-52 Engine General Information and Diagnosis:
DTC P0011 / P0012: “A” Camshaft Position - Timing Over-Advanced or System Performance / -
Retarded
S7RS0B1104014
System Description
Actual value of advanced valve timing does not reach target value.
Valve timing is advanced although ECM command is most retarding.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
WARNING!
• When performing a road test, select a place where there is no traffic or possibility of a traffic accident and be very careful during testing to avoid occurrence of an accident.
• Road test should be carried out by 2 persons, a driver and tester, on a level road.

NOTE
Check to make sure that the following conditions are satisfied when using this “DTC Confirmation
Procedure”.
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

1) Clear DTC. Refer to “DTC Clearance”.
2) Start engine and drive vehicle under usual driving condition for 5 minutes or longer until engine is warmed up to normal operating temperature.
3) Stop vehicle.
4) Run engine at idle speed for 1 minute.
5) Start vehicle and increase vehicle speed up to 80 km/h (50 mile/h).
6) Keep vehicle speed at 80 km/h (50 mile/h) for 1 minute or longer at 5th gear position or D range.
7) Decrease vehicle speed gradually.
8) Stop vehicle and turn OFF ignition switch.
9) Repeat Step 4) to 7) one time.
10) Stop vehicle. 11) Check DTC and pending DTC. DTC detecting condition
Trouble area
Actual value of advanced valve timing does not reach
target value, or valve timi ng is advanced although ECM
command is most retarding.
(2 driving cycle detection logic) • Oil control valve
• Oil galleries of timing sprocket
• Intake camshaft timing sprocket (Camshaft position
control (VVT) actuator)
• Oil control valve circuit
•ECM

Downloaded from www.Manualslib.com manuals search engine 1A-54 Engine General Information and Diagnosis:
DTC P0031 / P0032: HO2S Heater Control Circuit Low / High (Sensor-1)S7RS0B1104015
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature.
4) Run engine at idle speed for 1 min. or more.
5) Check DTC and pending DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

E23 C37
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
BLK/WHT
WHT
11
GRN
3 9
E23-29
WHT
YEL
BLK/WHT
BLKC37-46
C37-10
C37-57
6
7
10
BLK
BLUWHT
BLK/RED
4
5
8
12
1
I6RS0C110006-03
1. Main fuse box
4. Junction block assembly 7. Heater 10. To HO2S-2
2. Shield wire 5. “IG COIL” fuse8. To HO2S-2 heater 11. Individual circuit fuse box No.1
3. Ignition switch 6. HO2S-19. ECM 12. “IG ACC” fuse
DTC detecting condition Trouble area
HO2S-1 heater voltage is more than specified value or lower
than specified value for 5 seconds continuously.
(2 driving cycle detection logic) • HO2S-1 heater circuit
• HO2S-1 heater
•ECM

Downloaded from www.Manualslib.com manuals search engine 1A-56 Engine General Information and Diagnosis:
DTC P0037 / P0038: HO2S Heater Control Circuit Low / High (Sensor-2)S7RS0B1104016
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature.
4) Run engine at idle speed for 1 min.
5) Check DTC and pending DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

E23 C37
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
BLK/WHT
WHT
11
GRN
3 9
E23-29
BRN
YEL
BLK/WHT
BLKC37-47
C37-11
C37-57
6
2
7
10
BLK
BLUWHT
RED/BLU
1
4
5
8
12
5V
I6RS0C110007-01
1. Main fuse box 4. Junction block assembly 7. Heater 10. To HO2S-1
2. Shield wire 5. “IG COIL” fuse8. To HO2S-1 heater 11. Individual circuit fuse box No.1
3. Ignition switch 6. HO2S-29. ECM 12. “IG ACC” fuse
DTC detecting condition Trouble area
HO2S-2 heater voltage is more than specified value or less than
specified value for 5 seconds continuously
(2 driving cycle detection logic) • HO2S-2 heater
• HO2S-2 heater circuit
•ECM

Downloaded from www.Manualslib.com manuals search engine 1A-58 Engine General Information and Diagnosis:
DTC P0101: Mass or Volume Air Flow Circuit Range / PerformanceS7RS0B1104017
Wiring Diagram
DTC Detecting Condition and Trouble Area
E23C37
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
BLK/WHT
BLK/RED
BLK/RED
WHT
BLK/YELBLK/YEL
BLK/YEL
GRN
BRN/WHT
12V 5V
5V
2 3 4
E23-29
E23-60
E23-1
E23-16
BLK/ORN
BLKBLK
BLK/RED
BLK/YELGRY/BLU
ORN
1BLK/RED
5
E23-31BLK
ORN
GRY
GRN/BLK
C37-58
C37-15
C37-30
C37-26
C37-27
C37-25
C37-55
I6RS0C110014-01
1. MAF and IAT sensor
3. Main relay5. To other sensors
2. Ignition switch 4. ECM
DTC detecting condition Trouble area
• MAF volume is greater than 20 g/sec even if engine revolution is less than 900 rpm and intake manifold
pressure is less than 40 kPa (5.80 psi) with TP less than
1.5 °.
• MAF volume is lower than 10 g/sec even if engine
revolution is more than 2500 rpm and intake manifold
pressure is more than 60 kPa (8.70 psi) with TP more than
12 °.
(2 driving cycle detection logic) • Air intake system (clog or leakage)
• MAF sensor circuit
•MAF sensor
• TP sensor and/or its circuit
• MAP sensor and/or its circuit
•ECM

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-61
DTC P0102: Mass or Volume Air Flow Circuit Low InputS7RS0B1104018
Wiring Diagram
Refer to “DTC P0101: Mass or Volume Air Flow Circuit Range / Performance”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and run it for 10 sec.
4) Check DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

10 MAF sensor signal circuit check
1) Measure resistance between “GRN/BLK” wire terminal
of MAF and IAT sensor connector and “C37-26” terminal
of ECM connector.
Is resistance below 3
Ω? Faulty MAF and IAT
sensor.
“GRN/BLK” wire is open
or high resistance
circuit.
11 Is DTC P2135 detected? Go to “DTC P2135:
Throttle / Pedal Position
Sensor / Switch “A”/“B”
(Main / Sub) Voltage
Correlation”.Go to Step 12.
12 Is DTC P0106 displayed? Go to “DTC P0106:
Manifold Absolute
Pressure / Barometric
Pressure Circuit Range
/ Performance”.Substitute a known-
good ECM and recheck.
Step
Action YesNo
DTC detecting condition Trouble area
MAF sensor output voltage is less than 0.15 V for 0.5
seconds continuously
(1 driving cycle detection logic) • Open or short in MAF sensor circuit
• MAF sensor
•ECM
Step
Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 MAF sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Start engine and check MAF value displayed on scan tool. (Refer to “Scan Tool Data” for normal value.)
Is normal value indicated? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
Go to Step 3.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-63
DTC P0103: Mass or Volume Air Flow Circuit High InputS7RS0B1104019
Wiring Diagram
Refer to “DTC P0101: Mass or Volume Air Flow Circuit Range / Performance”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and run it for 10 sec.
4) Check DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

DTC detecting condition Trouble area
MAF sensor output voltage is higher than 4.85 V for 0.5 seconds
continuously.
(1 driving cycle detection logic) • Open or short in MAF sensor circuit
• MAF sensor
•ECM
Step
Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 MAF sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Start engine and check MAF value displayed on scan tool. (Refer to “Scan Tool Data” for normal value.)
Is normal value indicated? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
Go to Step 3.
3 MAF sensor power supply voltage check
1) Disconnect connector from MAF and IAT sensor with
ignition switch tuned OFF.
2) Turn ON ignition switch, measure voltage between engine ground and “BLK/RED” wire terminal of MAF and
IAT sensor connector.
Is voltage 10 – 14 V? Go to Step 4.
“BLK/RED” wire is open
circuit.
4 MAF sensor ground circuit check
1) Turn OFF ignition switch, measure resistance between
“GRY” wire terminal of MAF and IAT sensor connector
and engine ground.
Is resistance below 5
Ω? Go to Step 6. Go to Step 5.
5 Ground circuit check
1) Remove ECM from its br acket with ECM connectors
connected.
2) Measure resistance between “C37-27” terminal of ECM connector and engine ground.
Is resistance below 5
Ω? “GRY” wire is open or
high resistance circuit.
ECM grounds “E23-31”,
“C37-58”, “C37-15” and/
or “C37-30” circuit are
open or high resistance.
If wires are OK,
substitute a known-
good ECM and recheck.