Howo Mining Truck Dashboard Not Working | Troubleshooting & Repair Guide

If the dashboard of the Howo mining truck fails completely (black screen, stationary needles, no backlight or display data), the problem is usually caused by power supply failure, poor wiring contact, communication error or internal dashboard mainboard damage. Mining trucks work in dusty and bumpy conditions. The following troubleshooting steps go from simple to advanced, which can quickly resolve more than 95% of faults without complex equipment.

1. Basic Preliminary Inspection (No Tools Required, Priority Operation)

This step checks for manual errors and basic power issues and can be finished in 3 minutes.

1. Verify the vehicle power supply: Turn on the main battery switch and switch the ignition to the power-on position. Check if headlights and horn work normally. If there is no power for the whole vehicle, inspect battery terminals for looseness, oxidation or low charge. The battery voltage should stay stable at around 24V; low voltage will prevent the dashboard from powering up.

2. Check the dashboard lighting switch: Howo mining trucks have an independent dashboard lighting switch. If turned off by mistake, the screen will appear black as if the dashboard is dead. Toggle the switch to restore backlight.

3. Reboot the whole vehicle system: Bumps during operation may trigger temporary system glitches. Turn off the main power, wait 30 seconds and re-energize to clear transient circuit faults.

2. Power Supply System Troubleshooting (High-incidence Fault)

Blown fuses or broken power harnesses for the dashboard are common root causes. Focus on fuses and main power wiring.

1. Inspect the dedicated dashboard fuse: Open the fuse box under the driver’s seat, locate the dashboard fuse according to the manual. If the fuse is blown or blackened, replace it with an original fuse of the same rating. Never use a higher-rated fuse, which may burn wiring and the dashboard mainboard. If the new fuse blows again immediately, there is a short circuit in the wiring that needs further inspection.

2. Test the dashboard wiring harness: The main power connector of the Howo mining truck dashboard is Connector C1: Pin 7 is 24V power input, Pins 1/3 are ground wires. Remove the dashboard cover and unplug the rear main connector. Check for looseness, bent pins, oxidation, water ingress and dust buildup. Heavy dust and constant vibration on mining sites often lead to poor contact. Clean the pins with electronic contact cleaner and firmly re-seat the connector.

3. Check for damaged wiring and short circuits: Inspect the wiring harness under the steering wheel and inside the dashboard. Look for crushed, abraded or cracked insulation. Repair exposed wires with insulation tape, or replace heavily aged harnesses.

3. Communication and Control Module Troubleshooting

The Howo mining truck dashboard communicates with left and right body control modules. Broken communication will render the dashboard completely unresponsive.

1. Check communication wiring: Inspect the communication cables connecting the junction box under the dashboard to the body control modules. Confirm no loose connectors or broken wires. Normal operating voltage for communication should be 14–16V; abnormal voltage causes communication failure.

2. Body control module reset: If power supply and wiring are normal, the body control module may have temporary faults. Disconnect the negative battery terminal for 5 minutes to reset the module, then reconnect power and test the dashboard.

4. Internal Dashboard Assembly Repair

If external power and wiring are confirmed good, the fault lies inside the dashboard mainboard, a common issue caused by continuous vibration on mining trucks.

1. Mainboard cold solder joint repair (frequent fault): Long-term bumping causes cold solder joints on mainboard components such as crystal oscillators and CPU pins, leading to black screen and no response. Disassemble the dashboard assembly and re-solder the CPU pins and crystal oscillator pins on the mainboard to fix most internal circuit faults.

2. Backlight hardware damage: If the screen shows data but has no light, the backlight beads or lighting module are damaged. Replace the faulty beads or lighting components.

3. Dashboard assembly replacement: If the mainboard is burnt or chips are damaged, and re-soldering does not work, the dashboard assembly needs replacement. Release the spring clips on both sides of the dashboard, unplug the rear wiring connector, and install a matching original dashboard (Part No. WG9716580025). Reconnect the harness and fasten the clips.

5. Final Testing and Fault Prevention

1. After repair, power on and test backlight, gauges, tachometer, speedometer and warning lights to confirm all functions work before reassembly.

2. Due to harsh working conditions, regularly clean dust off dashboard connectors and secure harnesses to reduce loose connections and cold solder joints caused by vibration.

6. Repair Warnings

1. Do not use over-rated fuses or modify wiring arbitrarily, to avoid burning vehicle wiring and dashboard mainboard.

2. The dashboard mainboard contains precision electronic parts. Do not disassemble without soldering experience to prevent secondary damage.

3. If the fuse blows repeatedly or wires get hot due to short circuits, locate the short circuit in vehicle electrical systems instead of only replacing parts.