DTC 3-1-1
3-1-1 VEHICLE SPEED SENSOR SIGNALPreconditions for DTC
^ If engine speed exceeds 3320 rpm, the internal load signal is above 6.0 ms and road speed is below 2 km/h (1.24 mph) for 3 seconds, DTC 3-1-1 is set.
Substitute value
^ None.
Fault sources
^ Signal lead short circuited to ground or voltage supply.
^ Break in signal lead.
^ Contact resistance in connectors.
^ Defective Vehicle Speed Sensor (VSS).
^ Fault in sensor circuit.
Fault symptoms
^ No reading on speedometer, depending on fault source.
TESTING PROCEDURE
Check of Vehicle Speed Signal to Control Module
^ Test drive the car.
^ Look up the DTC parameter.
^ Read the VSS signal.
If speed is OK:
- Fault is intermittent. Proceed to: INTERMITTENT FAULT section below.
If speed is 0 mph:
- Fault is permanent. Proceed to: PERMANENT FAULT section below.
PERMANENT FAULT
Check of Speedometer
^ Test drive the car.
^ Check that the speedometer functions.
If the speedometer is OK:
- With VDO instrument panel:
Check the DTCs in the combined instrument panel.
- With Yazaki instrument panel:
Check the VSS.
If the speedometer shows 0 mph:
- Check the VSS signal.
Checking DTCs in the Combined Instrument Panel (VDO ONLY)
^ Switch Ignition ON.
^ Check if DTC 1-3-1 is stored in the combined instrument panel (using socket #7 on Data Link Connector "A").
If DTC 1-3-1 is stored:
- Check the lead between the combined instrument's connector A7 and ECM B18 for signs of short circuiting to voltage.
If DTC 1-3-1 is not stored:
- Check the VSS signal.
Checking the VSS Signal
^ Connect the measuring instrument and check the ground connectors.
^ Connect the ECM.
^ Gear lever in Neutral.
^ Raise the car so the front wheels are free off the ground.
^ Switch Ignition ON.
^ Connect a voltmeter between connectors #18 (ECM B18) and #28 (ECM B28) on the break-out box.
^ Rotate the front wheels.
The voltmeter reading should vary between approx. 0.5 Volts and above 5 Volts.
NOTE: When the rear wheels are at a standstill and the front wheels still spin, DTCs can be stored in the ABS system. Erase DTCs in the ABS system after fault tracing.
If reading is OK:
- The source of the DTC is poor contact in the ECM's connector.
- Rectify the connector with regard to contact resistance and oxidation.
If the voltmeter shows a steady reading of about 0 Volts:
- Check the lead between the combined instrument's connector A7 and ECM B18 for signs of short circuiting to ground.
If the voltmeter shows a steady reading above 5 Volts:
- With VDO instrument panel:
Check the lead between the combined instrument's connector A7 and ECM B18 for signs of a break.
- With Yazaki instrument panel:
Check the signal lead.
Checking the Signal Lead
^ Switch Ignition OFF.
^ Connect an ohmmeter between connectors #18 (ECM B18) and #28 (ECM B28) on the break-out box.
The ohmmeter should show approx. 500 ohms.
If the reading is OK:
- Check the lead between the combined instrument connector A7 and ECM B18 for signs of short circuiting to voltage.
If the reading differs:
- Check the lead between the combined instrument connector A7 and ECM B18 for signs of a break.
INTERMITTENT FAULT
Check of DTCs in the Combined Instrument Panel
^ Switch Ignition ON.
^ Check if DTC 1-3-1 is stored in the combined instrument panel (socket #7 on DLC "A").
If DTC 1-3-1 is stored:
- Check the lead between the combined instrument's connector A7 and ECM B18 for signs of intermittent short circuiting to voltage.
If DTC 1-3-1 is not stored:
- Fault tracing of the combined instrument and VSS circuit with regard to intermittent faults.
- Check the ECM's and combined instrument's connectors and connector 24/13 for signs of loose connection.
- Check the lead between the combined instrument's connector A7 and ECM B18 for signs of an intermittent disruption as well as intermittent short circuiting to ground.