With Integrated Fault-Diagnosis System (Flash Codes): 12243

Diagnostic procedure

1 Check that the speedometer is in working order and that the EDU shows plausible fuel consumption figures.

If the speedometer does not work, check the wiring and sensor.

Unplug the sensor's two-pin connector and measure the signal voltage from the speed sensor on the gearbox. The multimeter should be set for a.c.

When speed is increased the signal voltage should increase over a range of 0-5 V. If the wiring and sensor are Ok, change the speedometer.

If a varying voltage is not obtained, check the operation of the sensor (drive).

2 If the speedometer is OK but the EDU shows implausible fuel consumption figures, unplug the connector from the speedometer. Check:
- pin 1 - 3 = 12 V
- pin 1 - ground = 12 V
- pin 3 - ground = <1 ohm
If incorrect readings are obtained, check the wiring.

3 Remove the center pin from the speedometer connector. Plug the connector into the speedometer.

Take a reading across pins 2 and 3 at the same time as a wheel is rotated. A reading of 6 V or 0/12 V should be obtained. If the voltage reading is not OK, change the speedometer.

If the voltage reading is OK, unplug the EDU connector. Connect a Breakout Box to the car's wiring harness, LH control module not connected. Check the lead between pin 2 of the speedometer connector and pin 34 of the Breakout Box.

4 If the speedometer is OK and the EDU shows plausible fuel consumption figures, connect the Breakout Box to the car's wiring harness, LH control module not connected. With the ignition switched on, rotate a wheel. Check that 0/12 V or 6 V pulses are obtained on pin 34 of the Breakout Box.

If pulses are obtained, change the control module.

If pulses are not obtained, go to point 5.

5 Take a reading across pin 34 of the Breakout Box and pin 2 of the speedometer connector (connector not plugged into speedometer). Also check the lead's crimped connections.