Code No. P0842:
Malfunction of Secondary Pressure Sensor (low input)
DIAGNOSTIC FUNCTION
The CVT-ECU determines that the system is defective when the secondary pressure sensor output
voltage is lower than a predetermined value.
JUDGEMENT CRITERIA
The secondary 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 secondary pressure sensor)
- Damaged wiring harness and connectors
- Malfunction of CVT-ECU
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STEP 1. Voltage measurement at CVT-ECU connector (LPRS
terminal)
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(1)Drive the vehicle until the engine is warmed up.
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(2)Measure the CVT-ECU connector side by backprobing.
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(3)Selector lever position: N
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(5)Measure the voltage between the CVT-ECU connector (LPRS terminal) and body earth.
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Q.
Is the voltage approximately 0.09 V or less?
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 Go to Step 2.
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 Go to Step 8.
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STEP 2. Voltage measurement at CVT assembly connector (SSPW terminal)
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(1)Disconnect the CVT assembly connector, and measure at the wiring harness side.
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(2)Turn the ignition switch to the "ON" position.
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(3)Measure the voltage between the CVT assembly connector (SSPW terminal) and body
earth.
OK: approx. 5 V
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Q.
Is the check result normal?
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Go to Step 4.
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NO  : Go to Step 3.
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STEP 3. Check for open circuit or short to earth in SSPW line between
the CVT assembly connector and the CVT-ECU connector
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Q.
Is the check result normal?
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Go to Step 9.
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Repair the connector(s) or the wiring harness.
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STEP 4. Check for open circuit or short to earth in LPRS line between
the CVT assembly connector and the CVT-ECU connector
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Q.
Is the check result normal?
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Go to Step 5.
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Repair the connector(s) or the wiring harness.
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STEP 5. Check for open circuit in SGND line between the CVT assembly
connector and the CVT-ECU connector
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Q.
Is the check result normal?
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Go to Step 6.
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Repair the connector(s) or the wiring harness.
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STEP 6. Check for open circuit or short to earth in signal line between
the CVT assembly connector and the valve body harness connector (secondary pressure sensor line)
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Refer to  .
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Q.
Is the check result normal?
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Go to Step 7.
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Replace the valve body harness. (Refer to )
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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)
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Refer to .
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Q.
Is the check result normal?
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Replace the valve body assembly. (Refer to )
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Replace the valve body harness. (Refer to )
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STEP 8. Voltage measurement at CVT-ECU connector (LPRS terminal)
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(1)Drive the vehicle until the engine is warmed up.
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(2)Measure the CVT-ECU connector side by backprobing.
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(3)Selector lever position: N
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(5)Measure the voltage between the CVT-ECU connector (LPRS terminal) and body earth.
OK: approx. 1.67 -
1.69 V
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Q.
Is the check result normal?
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Go to Step 9.
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Replace the valve body assembly. (Refer to )
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STEP 9. Symptom recheck after erasing diagnosis code
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Q.
Is the diagnosis code set?
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Replace the CVT-ECU.
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Intermittent malfunction.
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