What are the reasons for the discrepancy between the odometer reading and the actual mileage?
1 Answers
The reasons for the discrepancy between the odometer reading and the actual mileage include a faulty odometer sensor, issues with the wiring between the sensor and the dashboard, or a malfunctioning dashboard pointer. Generally, the latter has a very low probability of occurring and can usually be ruled out. It is recommended that the driver visit a repair shop to have the odometer sensor inspected and replaced if necessary. Determining whether the issue is with the sensor or the dashboard: Disconnect the sensor connector, turn on the ignition, and locate the 2nd electrode connected to the brown wire with a red stripe in the connector. Use a homemade wire with a plug to extend it and lightly brush against a grounded part of the vehicle body to input a pulse signal to the dashboard. If the speedometer needle moves, it indicates that the dashboard is functioning properly. The fault lies with the sensor's reed switch or magnetic ring. If the speedometer needle does not move, it suggests an issue with the dashboard or the connecting wiring. Determining whether the issue is with the dashboard or the wiring: Remove the dashboard without disconnecting the plug, and use a multimeter to measure the three electrodes on the dashboard. Turn on the ignition, and check that the voltage from fuse No. 26 to the power supply line of the speedometer should be 12V when measured against the ground. Use the multimeter's resistance mode to measure; the resistance of the pulse signal line from the dashboard to the sensor connector should be zero, and the resistance of the ground electrode to the ground should also be zero. If the actual measurements do not match these three values, any short circuits in the wiring should be addressed. If the wiring is confirmed to be fault-free, the issue lies with the speedometer, which should be repaired or replaced as needed.
