DTC P0798, P0970, or P0971
Diagnostic Instructions
DTC Descriptors
| DTC P0798: Pressure Control Solenoid Valve 2
System Performance |
| DTC P0970: Pressure Control Solenoid Valve 2
Control Circuit Low Voltage |
| DTC P0971: Pressure Control Solenoid Valve 2
Control Circuit High Voltage |
Diagnostic Fault Information
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Pressure Control Solenoid Valve Control
|
P0970
|
P0798, P0971
|
P0798, P0971
|
-
|
Low Reference
|
-
|
P0798, P0971
|
P0798, P0971
|
P0798, P0971
|
|
| |
Typical Scan Tool Data
Pressure Control Solenoid Valve
Circuit
|
Short to Ground
|
Open
|
Short to Voltage
|
Operating Conditions: Engine running,
normal operating temperature
Parameter Normal Range: 100-1 100 mA
|
Pressure Control Solenoid Valve Control
|
0 mA
|
0 mA
|
2 550 mA
|
Low Reference
|
-
|
0 mA
|
1
|
1. Internal transmission control module (TCM) damage may occur if
shorted to B+
|
|
| |
Circuit/System Description
The shift control solenoid (SLC2) is installed on the front
valve body. The solenoid linearly control hydraulic pressure in
response to signals output from the transmission control module
(TCM). Through this, the SLC2 controls operating hydraulic pressure
to the clutch 2 for smooth shifting. According to each shift
control solenoid assembly, the transmission shifts from 1st gear
into 6th gear and vice versa. As a fail-safe function, if any shift
control solenoid assembly abnormality occurs, the TCM will disable
the current to the solenoids.
Conditions for Running the DTC
P0798
| • |
The ignition voltage is
between 10.2-15.5 V. |
| • |
The engine speed is greater
than 400 RPM for 2 s. |
| • |
The transmission is not in
emergency mode. |
| • |
TCM communication is
normal. |
| • |
DTCs P0970 and P0971 are not
set. |
P0970
| • |
The ignition voltage is
between 10.2-15.5 V. |
| • |
The engine speed is greater
than 400 RPM for 2 s. |
| • |
The transmission is not in
emergency mode. |
| • |
TCM communication is
normal. |
P0971
| • |
The ignition voltage is
between 10.2-15.5 V. |
| • |
The engine speed is greater
than 400 RPM for 2 s. |
| • |
The transmission is not in
emergency mode. |
| • |
TCM communication is
normal. |
Conditions for Setting the DTC
P0798
Deviation between commanded current and feedback current.
P0970
The TCM detects at least 5 times less than 23 mA current
consumption of the SLC2 control circuit for 100 ms.
P0971
The TCM detects at least 5 times more than 1.333 A current
consumption of the SLC2 control circuit for 100 ms.
Action Taken When the DTC Sets
P0798
| • |
DTC P0798 is a Type B
DTC. |
| • |
The TCM turns OFF all
solenoids. |
| • |
The TCM allows the vehicle
after a stop to operate only in the second gear and "R"
range. |
P0970, P0971
| • |
DTCs P0970 and P0971 are Type
B DTCs. |
| • |
No self learning
function. |
| • |
The TCM turns OFF all
solenoids. |
| • |
The TCM allows the vehicle
after a stop to operate only in the second gear and "R"
range. |
Conditions for Clearing the DTC
P0798
| • |
DTC P0798 is a Type B
DTC. |
| • |
The TCM detects the error
current less than 50 mA for 2.75 ms. |
P0970, P0971
| • |
DTCs P0970 and P0971 are Type
B DTCs. |
| • |
The current consumption of the
SLC2 control circuit is 0.1-1.1 A for 500 ms. |
Diagnostic Aids
When attempting to set solenoid electrical DTCs, ensure the TCM
is warmed up and the transmission is operated in 2nd gear long
enough to ensure a 3°C (5°F) increase in TCM substrate
temperature. This will place the TCM under the optimal conditions
to test solenoid electrical DTCs.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
Description and Operation
Transmission Component and System Description
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
| 1. |
Ensure the transmission fluid
temperature is between 50-80°C (122-176°F). |
| 2. |
Operate the vehicle in 2nd
gear long enough to ensure at least a 3°C (5°F) rise in
transmission fluid temperature, then operate the vehicle in Park
for 5 s. |
| 3. |
Observe the scan tool Clutch
Pressure Control Solenoid Valve 2 Current parameter, the reading
should be between 0.1-1.1 A. |
Circuit/System Testing
Command the Clutch Pressure Control Solenoid Valve 2 with a scan
tool. The value should change from 0.0-1.0 A.
If the value does not change, turn ignition OFF, remove the K71
Transmission Control Module. Connect a test lamp between the low
reference circuit terminal 18 X2 at the K71 Transmission Control
Module and the voltage supply component circuit terminal 17 X2 at
the K71 Transmission Control Module. Command the Clutch Pressure
Control Solenoid Valve 2 with a scan tool. The test lamp has to
illuminate brighter with increasing current. If the test lamp
always illuminate or always does not illuminate, replace the K71
Transmission Control Module.
Component Testing
Static Test
| 1. |
Ignition OFF, remove the K71
Transmission Control Module. |
| 2. |
Test for 5-5.6 Ω at
20°C (68°F) between the low reference circuit terminal 18
X2 and the voltage supply circuit terminal 17 X2. |
| ⇒ |
If less than the specified range, test the wiring
harness for internal short. If the circuit test normal, replace the
Q27B Pressure Control Solenoid Valve 2. |
| 3. |
Test for infinite resistance
between each terminal and the low reference circuit terminal 18 X2
and also to the voltage supply circuit terminal 17 X2. |
| ⇒ |
If less than the specified range, replace the
wiring harness. |
| ⇒ |
If the inspection test normal, replace the control
valve body. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic
procedure.
|
