Code No. P0847:
Malfunction of Primary Pressure Sensor (low input)
DIAGNOSTIC FUNCTION
The CVT-ECU determines that the system is defective when the primary pressure sensor output voltage
is lower than a predetermined value.
JUDGEMENT CRITERIA
The primary pressure sensor detects a voltage of 0.09 V or less for five seconds with
the CVT fluid temperature more than -20°C.
PROBABLE CAUSES
- Malfunction of the valve body assembly (Faulty primary pressure sensor)
- Damaged wiring harness and connectors
- Malfunction of CVT-ECU
|
|
STEP 1. Voltage measurement at CVT-ECU connector (PRPS
terminal)
|
|
|
(1)Drive the vehicle until the engine is warmed up.
|
|
|
(2)Measure the CVT-ECU connector side by backprobing.
|
|
|
(3)Selector lever position: N
|
|
|
(5)Measure the voltage between the CVT-ECU connector (PRPS terminal) and body earth.
|
|
|
Q.
Is the voltage approximately 0.09 V or less?
|
|
|
 Go to Step 2
|
|
|
|
|
|
 Go to Step 8
|
|
|
|
|
|
STEP 2. Voltage measurement at CVT assembly connector (SSPW terminal)
|
|
|
(1)Disconnect the CVT assembly connector, and measure at the wiring harness side.
|
|
|
(2)Turn the ignition switch to the "ON" position.
|
|
|
(3)Measure the voltage between the CVT assembly connector (SSPW terminal) and body
earth.
OK: approx. 5 V
|
|
|
Q.
Is the check result normal?
|
|
|
Go to Step 4
|
|
|
|
|
|
NO  : Go to Step 3
|
|
|
|
|
|
STEP 3. Check for open circuit or short to earth in SSPW line between
the CVT assembly connector and the CVT-ECU connector
|
|
|
Q.
Is the check result normal?
|
|
|
Go to Step 9.
|
|
|
|
|
|
Repair the connector(s) or the wiring harness.
|
|
|
|
|
|
STEP 4. Check for open circuit or short to earth in PRPS line between
the CVT assembly connector and the CVT-ECU connector
|
|
|
Q.
Is the check result normal?
|
|
|
Go to Step 5
|
|
|
|
|
|
Repair the connector(s) or the wiring harness.
|
|
|
|
|
|
STEP 5. Check for open circuit in SGND line between the CVT assembly
connector and the CVT-ECU connector
|
|
|
Q.
Is the check result normal?
|
|
|
Go to Step 6
|
|
|
|
|
|
Repair the connector(s) or the wiring harness.
|
|
|
|
|
|
STEP 6. Check for open circuit or short to earth in signal line between
the CVT assembly connector and the valve body harness connector (primary pressure sensor line)
|
|
|
Refer to  .
|
|
|
Q.
Is the check result normal?
|
|
|
Go to Step 7
|
|
|
|
|
|
Replace the valve body harness (Refer to ).
|
|
|
|
|
|
STEP 7. Check for open circuit or short to earth in power supply line
between the CVT assembly connector and the valve body harness connector (sensor power supply
line)
|
|
|
Refer to .
|
|
|
Q.
Is the check result normal?
|
|
|
Replace the valve body assembly (Refer to ).
|
|
|
|
|
|
Replace the valve body harness (Refer to ).
|
|
|
|
|
|
STEP 8. Voltage measurement at CVT-ECU connector (PRPS terminal)
|
|
|
(1)Drive the vehicle until the engine is warmed up.
|
|
|
(2)Measure the CVT-ECU connector side by backprobing.
|
|
|
(3)Selector lever position: N
|
|
|
(5)Measure the voltage between the CVT-ECU connector (PRPS terminal) and body earth.
OK: approx. 0.90 - 0.92 V
|
|
|
Q.
Is the check result normal?
|
|
|
Go to Step 9
|
|
|
|
|
|
Replace the valve body assembly (Refer to ).
|
|
|
|
|
|
STEP 9. Symptom recheck after erasing diagnosis code
|
|
|
Q.
Is the diagnosis code set?
|
|
|
Replace the CVT-ECU.
|
|
|
|
|
|
Intermittent malfunction.
|
|
|
|