CONTINUOUSLY VARIABLE TRANSMISSION (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P0971 PRESSURE CONTROL SOLENOID "C" CONTROL CIRCUIT HIGH
DTC detecting condition:
Immediately at fault recognition
Trouble symptom:
• Tight corner braking phenomenon occurs.
• Drivability getting worse.
CAUTION:
Use the check board when measuring the TCM terminal voltage and resistance.
Wiring diagram:
CVT control system CVT Control System">

| STEP | CHECK | YES | NO |
1.CHECK HARNESS.
1) Turn the ignition switch to OFF.
2) Disconnect the TCM connector.
3) Disconnect the transmission connector.
4) Measure the resistance between TCM connector and transmission connectors.
Connector & terminal
(B54) No. 48 — (B11) No. 8:
Is the resistance less than 1 ??
Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P0971 PRESSURE CONTROL SOLENOID "C" CONTROL CIRCUIT HIGH">Go to Step 2.
Repair the open circuit of harness.
2.CHECK HARNESS.
1) Turn the ignition switch to ON.
2) Measure the voltage between TCM connector and chassis ground.
Connector & terminal
(B54) No. 48 (+) — Chassis ground (−):
Is the voltage approx. 0 V?
Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P0971 PRESSURE CONTROL SOLENOID "C" CONTROL CIRCUIT HIGH">Go to Step 3.
Repair the short circuit of harness.
3.CHECK AWD SOLENOID.
Measure the resistance between transmission connector and transmission body.
Connector & terminal
(T4) No. 8 — Transmission body:
Is the resistance approx. 2 — 4.5 ?? (when cold)
Check for poor contact of connector, and if no fault is found, replace the TCM. Transmission Control Module (TCM)">
Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P0971 PRESSURE CONTROL SOLENOID "C" CONTROL CIRCUIT HIGH">Go to Step 4.
4.CHECK HARNESS INSIDE TRANSMISSION.
CAUTION:
Start work after ATF cools down.
1) Remove the transmission valve cover.
2) Check for the harness pinch, damage.
Is there any fault in the harness?
Replace the transmission harness.
Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P0971 PRESSURE CONTROL SOLENOID "C" CONTROL CIRCUIT HIGH">Go to Step 5.
5.CHECK HARNESS INSIDE TRANSMISSION.
1) Disconnect the control valve body connector.
2) Turn the ignition switch to ON.
3) Measure the voltage between transmission connector and transmission body.
Connector & terminal
(T4) No. 8 (+) — Transmission body (−):
Is the voltage approx. 0 V?
Replace the control valve body. Control Valve Body">
Replace the transmission harness.
1. OUTLINE OF DIAGNOSIS
• Detect open circuit or power supply-output short circuit in the transfer solenoid circuit.
• Judge as NG if an open circuit or a short circuit to ground is detected more than 10 times via the detection circuit in the transfer solenoid drive circuit.
2. EXECUTION CONDITION
Secondary Parameters | Execution condition |
Target duty cycle | 100% |
3. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Malfunction Criteria | Threshold Value |
Malfunction signal from solenoid driver IC | ≥ 10 count |
Time Needed for Diagnosis: Immediately
Malfunction Indicator Light Illumination: Does not illuminate.
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