ON-BOARD DIAGNOSTIC (OBD) SYSTEM DESCRIPTION [JA5A-EL]


BME050200000T10

• The OBD system has the following functions:
- Failure detection function: detects failure of the input/output devices and system components of the ATX.
- Memory function: stores the DTC when a failure is detected.
- Fail-safe function: fixes the output device function and input value of the sensors/switches to ensure minimum vehicle drivability when a failure is detected.
- PID data monitoring function: monitors the input/output signal and calculated value of the TCM and sends the monitoring data to the scan tool.

Block Diagram

DTC Comparison Lists

• The following codes are divided to improve serviceability.

Part Name

DTC

Definition

Transaxle range switch
P0705
Circuit malfunction (power short)
P0706
Circuit malfunction (open/ground short)
Transaxle fluid temperature sensor
P0711
Malfunction (stuck): for Israeli specs.
N/A: except for Israeli specs.
P0712
Circuit malfunction (short)
P0713
Circuit malfunction (open)
Input/turbine speed sensor
P0715
Circuit malfunction (open/short)
Vehicle speedometer sensor
P0720
Circuit malfunction (open/short)
Torque converter
P0740
Circuit malfunction: for Israeli specs.
N/A: except for Israeli specs.
TCC control solenoid valve
P0743
Circuit malfunction (open/short)
Pressure control solenoid
P0748
Circuit malfunction (open/short)
Shift solenoid A
P0751
Malfunction (stuck off): for Israeli specs.
N/A: except for Israeli specs.
P0752
Malfunction (stuck on): for Israeli specs.
N/A: except for Israeli specs.
P0753
Circuit malfunction (open/short)
Shift solenoid B
P0756
Malfunction (stuck off): for Israeli specs.
N/A: except for Israeli specs.
P0757
Malfunction (stuck on): for Israeli specs.
N/A: except for Israeli specs.
P0758
Circuit malfunction (open/short)
Shift solenoid C
P0761
Malfunction (stuck off): for Israeli specs.
N/A: except for Israeli specs.
P0762
Malfunction (stuck on): for Israeli specs.
N/A: except for Israeli specs.
P0763
Circuit malfunction (open/short)
Reduction timing solenoid valve
P0768
Circuit malfunction (open/short)
Neutral shift solenoid valve
P0773
Circuit malfunction (open/short)
2-4 brake solenoid valve
P0778
Circuit malfunction (open/short)
Intermediate sensor
P0791
Circuit malfunction (open/short)
High clutch solenoid valve
P0798
Circuit malfunction (open/short)
GND return
P1710
Circuit malfunction (open)
CAN
U0073
CAN BUS OFF
CAN
U0100
TCM cannot receive any signals from PCM

Failure Detection Function

• The failure detection function detects failures in the input/output signal system (when the IG switch is on or while driving).
• When a failure is detected, the DTCs in the DTC chart are outputted to FAT terminal in the DLC through the failure indication function. At the same time, the failure detection results are sent to the fail-safe function and the memory function.
• If a failure is detected, the HOLD indicator light flashes or illuminates to warn the driver of a malfunction in the powertrain system components or sensor/switches. (Also, MIL will be illuminated except for DTC P0748)

Memory Function

• The memory function stores the signal systems that are determined as failures by the failure detection function. The memory is not erased even if the IG switch is turned off (LOCK position) or the detected failures are recovered.
• To clear the stored failure information, disconnect the negative battery cable.

Failure Indication Function

• The signal system which has been judged to be abnormal by the failure detection function is sent to the HOLDF indicator light and DLC (FAT terminal) as a DTC.

When using voltmeter

• The DTC can be checked by fluctuation of the voltmeter needle.
• Each DTC consists of four digits. These numbers are indicated by four separate indication of two-digit number, a combination of "1" and each number of the code.

When using HOLD indicator light

• When the TAT terminal is shorted after the IG switch is turned on, the HOLD indicator light indicates the DTCs.
• Each DTC consists of four digits. These numbers are indicated by four separate indication of two-digit number, a combination of "1" and each number of the code.

DTC Table

DTC No.

On-board diagnostic function

MIL

HOLD indicator light flash

DC

Monitor item

Memory function

P0705
TR switch circuit malfunction (power short circuit)
ON
YES
2
CCM
X
P0706
TR switch circuit malfunction (open/ground short circuit)
ON
YES
2
CCM
X
P0711*
TFT sensor malfunction (stuck)
ON
NO
2
CCM
X
P0712
TFT sensor circuit malfunction (short circuit)
ON
YES
2
CCM
X
P0713
TFT sensor circuit malfunction (open circuit)
ON
YES
2
CCM
X
P0715
Input/turbine speed sensor circuit malfunction
ON
YES
2
CCM
X
P0720
Vehicle speedometer sensor circuit malfunction
ON
YES
2
CCM
X
P0740*
TCC system
ON
NO
2
CCM
X
P0743
TCC solenoid valve malfunction (open/short)
ON
YES
1
CCM
X
P0748
Pressure control solenoid malfunction (open/short)
OFF
YES
-
CCM
X
P0751*
Shift solenoid A malfunction (stuck off)
ON
NO
2
CCM
X
P0752*
Shift solenoid A malfunction (stuck on)
ON
NO
2
CCM
X
P0753
Shift solenoid A malfunction (open/short)
ON
YES
1
CCM
X
P0756*
Shift solenoid B malfunction (stuck off)
ON
NO
2
CCM
X
P0757*
Shift solenoid B malfunction (stuck on)
ON
NO
2
CCM
X
P0758
Shift solenoid B malfunction (open/short)
ON
YES
1
CCM
X
P0761*
Shift solenoid C malfunction (stuck off)
ON
NO
2
CCM
X
P0762*
Shift solenoid C malfunction (stuck on)
ON
NO
2
CCM
X
P0763
Shift solenoid C malfunction (open/short)
ON
YES
1
CCM
X
P0768
Reduction timing solenoid malfunction (open/short)
OFF
YES
-
CCM
X
P0773
Neutral shift solenoid malfunction (open/short)
OFF
YES
-
CCM
X
P0778
2-4 brake solenoid malfunction (open/short)
OFF
YES
-
CCM
X
P0791
Intermediate sensor malfunction (open/short)
ON
YES
2
CCM
X
P0798
High clutch solenoid malfunction (open/short)
OFF
YES
-
CCM
X
P1710
GND return malfunction
OFF
NO
-
Other
X
U0073
CAN BUS OFF
ON
YES
1
CCM
X
U0100
TCM cannot receive any signals from PCM
ON
YES
1
CCM
X

X :
Available
* :
Israeli specs.

Fail-safe Function

• In the fail-safe function, minimum vehicle drivability is obtained by changing the signals that are determined as malfunctions by the failure detection function to the preset values, and limiting the TCM control.

DTC No.

On-board diagnostic function

Detection condition

Fail-safe

TCC

HOLD mode selection

P0705
Transaxle range (TR) switch circuit malfunction (power short circuit)
• Two or more range signals are inputted from TR switch for 5 seconds or more
• TR switch priority
D > N > P > R > S > L
• Inhibits feedback control, SLOPE mode, torque reduction control
Available
Available
P0706
Transaxle range (TR) switch circuit malfunction (open/ground short circuit)
• No range signal is inputted from TR switch for 100 seconds or more
• Inhibits feedback control, SLOPE mode, torque reduction control
Available
Available
P0711*
Transaxle fluid temperature (TFT) sensor malfunction (stuck)
• TFT sensor signal stays outside normal temperature range for 10 minute or more
-
Available
Available
P0712
Transaxle fluid temperature (TFT) sensor circuit malfunction (short circuit)
• Signals form TFT sensor are 155 °C {311 °F} or greater for 10 min.
• Inhibits feedback control
• Engine coolant temperature signal are used for shifting.
Available
Available
P0713
Transaxle fluid temperature (TFT) sensor circuit malfunction (open circuit)
• Vehicle speed is 20 km/h {12.4 mph} or greater, and signals from TFT sensor are -30 °C {-22 °F} or less for 150 seconds or more
Available
Available
P0715
Input/turbine speed sensor circuit malfunction
• Input/turbine speed sensor is 600 rpm or less while engine speed is 1500 rpm or greater and vehicle speed is 40 km/h {24.8 mph} or greater in D, S, or L ranges.
• Inhibits shift control
Available
Available
P0720
Vehicle speedometer sensor circuit malfunction
• Vehicle speedometer sensor is 150 rpm or less while intermediate sensor 1400 rpm or greater in D, S, or L range for 2 second or more.
• Inhibits SLOPE mode, feedback control, torque reduction control
Available
Available
P0740*
Torque converter clutch (TCC) system
• RPM difference between crankshaft (engine speed signal) and reverse clutch drum (input/turbine speed sensor signal) exceeds the pre-programmed value
-
Available
Available
P0743
Torque converter clutch (TCC) solenoid valve malfunction (open/short)
• Open or short in torque converter clutch solenoid valve circuit (Voltage different from on/off signal relayed by CPU in TCM is detected while TCM is monitoring solenoid output voltage.)
• Stops driving of TCC solenoid valve (OFF)
Inhibition
Available
P0748
Pressure control solenoid malfunction (open/short)
• Open or short in pressure control solenoid circuit (Voltage different from on/off signal relayed by CPU in TCM is detected while TCM is monitoring solenoid output voltage.)
• Stops driving of pressure control solenoid, 2-4 brake solenoid valve, and high clutch solenoid valve (OFF)
• Inhibit feedback control.
Available
Available
P0751*
Shift solenoid A malfunction (stuck off)
• Difference between actual gear ratio and gear ratio set in TCM is large
-
Available
Available
P0752*
Shift solenoid A malfunction (stuck on)
• Difference between actual gear ratio and gear ratio set in TCM is large
-
Available
Available
P0753
Shift solenoid A malfunction (open/short)
• Open or short in shift solenoid A circuit (Voltage different from on/off signal relayed by CPU in TCM is detected while TCM is monitoring solenoid output voltage.)
• Stops driving all ON/OFF type solenoids (OFF) and TCC solenoid valve (OFF)
Inhibition
Inhibition
P0756*
Shift solenoid B malfunction (stuck off)
• Difference between actual gear ratio and gear ratio set in TCM is large
-
Available
Available
P0757*
Shift solenoid B malfunction (stuck on)
• Difference between actual gear ratio and gear ratio set in TCM is large
-
Available
Available
P0758
Shift solenoid B malfunction (open/short)
• Open or short in shift solenoid B circuit (Voltage different from on/off signal relayed by CPU in TCM is detected while TCM is monitoring solenoid output voltage.)
• Stops driving all ON/OFF type solenoids (OFF) and TCC solenoid valve (OFF)
Inhibition
Inhibition
P0761*
Shift solenoid C malfunction (stuck off)
• Difference between actual gear ratio and gear ratio set in TCM is large
-
Available
Available
P0762*
Shift solenoid C malfunction (stuck on)
• Difference between actual gear ratio and gear ratio set in TCM is large
-
Available
Available
P0763
Shift solenoid C malfunction (open/short)
• Open or short in shift solenoid C circuit (Voltage different from on/off signal relayed by CPU in TCM is detected while TCM is monitoring solenoid output voltage.)
• Stops driving all ON/OFF type solenoids (OFF) and TCC solenoid valve (OFF)
Inhibition
Inhibition
P0768
Reduction timing solenoid valve malfunction (open/short)
• Open or short in reduction timing solenoid valve circuit (Voltage different from on/off signal relayed by CPU in TCM is detected while TCM is monitoring solenoid output voltage.)
• Stops driving of reduction timing solenoid valve (OFF)
Available
Available
P0773
Neutral shift solenoid valve malfunction (open/short)
• Open or short in neutral shift solenoid valve circuit (Voltage different from on/off signal relayed by CPU in TCM is detected while TCM is monitoring solenoid output voltage.)
• Stops driving of neutral shift solenoid valve (OFF)
Available
Available
P0778
2-4 brake solenoid valve malfunction (open/short)
• Open or short in 2-4 brake solenoid valve circuit (Voltage different from on/off signal relayed by CPU in TCM is detected while TCM is monitoring solenoid output voltage.)
• Stops driving of pressure control solenoid, 2-4 brake solenoid valve, and high clutch solenoid valve (OFF)
• Inhibit feedback control.
Available
Available
P0791
Intermediate sensor malfunction (open/short)
• Rotation speed of output gear (intermediate sensor) is low when vehicle speed and engine speed exceed the pre programmed value
• Inhibit feedback control
• Inhibits torque reduction control
Available
Available
P0798
High clutch solenoid valve malfunction (open/short)
• Open or short in high clutch solenoid valve circuit (Voltage different from on/off signal relayed by CPU in TCM is detected while TCM is monitoring solenoid output voltage.)
• Stops driving of pressure control solenoid, 2-4 brake solenoid valve, and high clutch solenoid valve (OFF)
• Inhibit feedback control.
Available
Available
P1710
GND return malfunction
• TCM detects open in GND return signal of solenoid.
-
Available
Available
U0073
CAN BUS OFF
• CAN controller damaged.
• Throttle valve opening angle is fixed (4/8) at the time in order to determine shift
• Maximizes line pressure
Inhibition
Available
U0100
TCM cannot receive any signals from PCM
• TCM cannot receive any signals from PCM

* :
Israeli specs.

Parameter Identification (PID) Access

Monitor item table

Display on the tester

Definition

Unit/Condition

TCM terminal

24B_Duty
2-4 brake solenoid valve control signal in TCM
%
2V
BOO TCM
Brake switch
on/off
1U
PNP_TCM
TR switch (P/N position switch)
Drive/Neutral
-
FAT
FAT terminal (DLC in engine compartment)
on/off
1Q
GEAR
Calculated gear range in TCM
1/2/3/4/5
-
HC_Duty
High clutch solenoid valve control signal in TCM
%
2U
LPS
Pressure control solenoid control signal in TCM
%
2Y
N_SFT
Neutral shift solenoid valve control signal in TCM
on/off
2D
OSS
Intermediate sensor
RPM
1K, 1X
RDCN_TIM
Reduction timing solenoid valve control signal in TCM
on/off
2G
RPM_TCM
Engine speed
RPM
-
SSA/SS1
Shift solenoid A control signal in TCM
on/off
-
SSB/SS2
Shift solenoid B control signal in TCM
on/off
-
SSC/SS3
Shift solenoid C control signal in TCM
on/off
-
TAT
TAT terminal (DLC in engine compartment)
on/off
1A
TCCC
TCC solenoid valve control signal in TCM
%
2S
TCIL
HOLD indicator light control signal in TCM
on/off
1E
TCS
HOLD switch
on/off
2I
TFT
ATF temperature
°C, °F
1B, 1F
TFTV
ATF temperature signal voltage
V
1B, 1F
THOP
Throttle position
%
-
TRD
Tr switch (D range switch)
on/off
1Z
TRL
TR switch (L range switch)
on/off
2C
TRR
TR switch (R position switch)
on/off
1W
TRS
TR switch (S range switch)
on/off
1AA
TSS
Input/turbine speed sensor
RPM
1N, 2F
VPWR_TCM
Battery voltage
V
1P
VSS_TCM
Vehicle speed
KPH, MPH
1V, 1M