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OBD-II Unit Not Receiving Power

What to do if your OBD-II tracking device isn't powering on or connecting to your vehicle.

Updated this week

When you plug your tracking unit into the OBD-II port, the device should beep once to confirm it's receiving power. If there's no beep, the device isn't getting power.

Quick Check First

The most common cause is loose connections. Check that the device or cable is fully plugged in to the OBD-II port.

Direct Connection Troubleshooting

If you're plugging the device directly into the OBD-II port:

  1. Unplug the tracker completely

  2. Plug it back in firmly

  3. Listen for the beep

Extension Cable Troubleshooting

If you're using an OBD-II extension cable, try these steps in order:

Check Cable to Port Connection

  1. Turn off the engine

  2. Unplug the cable from the vehicle's OBD-II port

  3. Wait 5 minutes

  4. Plug it back in firmly

  5. Listen for the beep

Check Unit to Cable Connection

If no beep after step 1:

  1. Turn off the engine

  2. Unplug the unit from the cable

  3. Wait 5 minutes

  4. Plug the unit back into the cable

  5. Listen for the beep

Test if the Unit Works

To isolate whether the problem is the cable or unit:

  1. Disconnect the cable from both the OBD-II port and unit

  2. Plug the unit directly into the OBD-II port

  3. If it beeps, the problem is the cable or its fuse

Check the Cable Fuse

Extension cables have a 3A mini-blade fuse (available at auto parts stores):

  1. Open the fuse holder cap

  2. Remove the fuse

  3. Test with a multimeter or replace the fuse

  4. With cable connected to OBD-II port and unit, insert the replacement fuse

Advanced Troubleshooting

Check OBD-II Port Power

Use a digital multimeter to test the OBD-II port voltage on:

  • Pin 16 (power)

  • Pin 4 (chassis ground)

  • Pin 5 (signal ground)

Check Vehicle Fuses

If the multimeter shows 0 volts, check for blown fuses. The OBD-II port is often fused on the auxiliary circuit (usually labelled as "cigarette" on the fuse panel diagram).

If both the OBD-II port and power fuses are fine, the cable or unit may need replacement.

Still Having Problems?

If you've tried all these steps and the unit still isn't receiving power, contact our support team. They can perform additional troubleshooting and arrange a technician visit if needed.

Have this information ready:

  • Vehicle name and model

  • Date and time of last report from RAM Tracking

  • On-site contact name

  • Engineer visit location (if necessary)

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