P0502

DTC P0502 Vehicle Speed Sensor Circuit Low Input (1 Of 2):

DTC P0502 Vehicle Speed Sensor Circuit Low Input (2 Of 2):

Vehicle Speed Sensor Circuit:

CIRCUIT DESCRIPTION
Circuit 439 is the ignition voltage feed for the PCM. Circuit 440 is the battery feed for the PCM. When the PCM detects a low voltage, a high voltage for a long time, or a high voltage for a short time, then DTC P0560 sets. DTC P0560 is a type D DTC.


CONDITIONS FOR SETTING THE DTC

System Voltage Low:

^ The engine speed is greater than 1500 RPM.
^ The system voltage is less than 10.5 volts at a maximum transmission temperature of 152°C (305°F).
^ The system voltage is less than 6.7 volts at a minimum transmission temperature of -40°C (-40°F).
^ All conditions met for 4 seconds.

If the system voltage is high then the system voltage is greater than 19 volts for 4 seconds.

ACTION TAKEN WHEN THE DTC SETS

^ The PCM causes an immediate landing to second gear.
^ The PCM turns off the Pressure Control Solenoid Valve (PC Sol. Valve).
^ The PCM inhibits the Torque Converter Clutch (TCC) engagement.
^ The PCM freezes the shift adapts.
^ The PCM does NOT illuminate the Malfunction Indicator Lamp (MIL).

CONDITIONS FOR CLEARING THE DTC

^ A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported.
^ The PCM cancels the DTC default actions when the fault no longer exists.
^ The PCM cancels the DTC default actions when the ignition is cycled OFF long enough to power down the PCM.

DIAGNOSTIC AIDS

^ Charging the battery with a battery charger and jumpstarting an engine may set DTCs.
^ If this DTC is set when an accessory is operated, inspect for faulty connections or an excessive current draw.
^ Inspect for faulty electrical connections at the starter solenoid.
^ Inspect for faulty electrical connections at the fusible link.
^ Inspect for loose or damaged terminals at the generator.
^ Inspect the generator belt wear and the generator belt tension.
^ First diagnose and clear any engine DTCs or Accelerator Pedal Position (APP) Sensor codes that are present. Then inspect for any transmission DTCs that may have reset.

TEST DESCRIPTION
4. Step 4 tests the charging system voltage.
5. Step 5 tests the battery voltage input at the PCM.
7. Step 7 tests the ignition voltage inputs at the PCM.