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Compiled automatically from service literature and owner experience. Specs are for the typical configuration — check them against your exact car before you start.

Nissan Vanette (1st generation): Diagnosing No Low Beam and High Beam, Circuit Overview

When low beam and high beam both go out at the same time, the cause is almost always a shared part of the circuit, not the bulbs. This means the fuses, relay, combination switch, shared ground or supply wire. I did not confirm a complete factory wiring diagram for your exact trim level, so below is the typical circuit layout and the order for testing it.

Difficulty: Medium Time: 1-2 hours Steps: 9 Tools: Multimeter or 12 V test light, wrench and screwdriver set, fuse and relay kit, jumper wire with an inline fuse if needed

Part

  • 🔩 Typical candidates, if the cause is in them: headlight fuses, headlight relay, combination (turn signal/light) switch, headlight connectors and plugs, ground terminal. Exact part numbers for your trim level are not confirmed, so the parts are listed without codes

Step by step

9 steps
  1. Typical circuit layout. Battery positive goes to the headlight fuse or fusible link. From there it goes to the headlight relay contacts or directly to the combination switch. Then current flows through the switch (the "parking lights / low beam / high beam" positions and the flash-to-pass function) and through separate left and right headlight fuses to the bulbs. Each headlight gets its ground from a separate wire to the body. On many Vanette versions, low and high beam are powered through a shared fuse or relay. So a simultaneous failure of both functions points to this shared part.
  2. Fuse boxes. The main box is under the instrument panel on the driver's left. The headlight fuses (left and right, low and high beam) may be located separately on either side. An additional box with high-current fuses and a fusible link is in the engine compartment or near the battery. The location depends on the version, so check both places. Check the fuse marked HEAD or "headlights" and the whole group next to it. Compare the rating with the box cover and replace only with the same rating. For the shared headlight circuit this is usually 20-30 A.
  3. Checking the fuses. Do not rely on appearance alone. Test each fuse with a multimeter, or check the voltage at both of its terminals with the lights on. If a new fuse blows right away, look for a short circuit. Most often it is chafed wiring near the headlights, near the hood hinges or near the connectors. Never install a fuse with a higher rating.
  4. Headlight relay. If the circuit has a relay, remove it and test it. Apply 12 V to the coil, and the contacts should click and close. For a quick check, swap it with an identical relay from another circuit, for example the horn. Clean any oxidized terminals in the relay socket.
  5. Checking power and ground at the headlight. Unplug the headlight connector. With the low beam on, you should see about 12 V between the low beam pin and the body. Check the same with the high beam on. If voltage is present but the bulb does not light, check the ground. Test the connector's ground pin to the body for continuity. A bad ground or an oxidized terminal often causes a complete loss of light on both headlights.
  6. Combination (headlight) switch. If there is no voltage at the headlights but voltage is present at the switch input, the switch itself or its connector is faulty. Check the switch contacts for burning and the connector for melting. To do this, remove the steering column cover. On older vehicles, melted connector terminals are common. Clean them or replace the connector, and if worn, replace the whole switch.
  7. Checking the supply wire. Check the voltage at the switch's power terminal and after the relay. If it is present before the fusible link and missing after it, the link has burned out. Inspect the connectors at the battery and at the relay, as well as the harness near the hood. Oxidation and burned contacts are common there.
  8. If one function works through the flash-to-pass (brief high beam) but the steady light does not come on, the problem is in the switch itself or in the relay control circuit. If neither the parking lights nor the headlights work, look for a shared positive supply.
  9. Reassembly and testing. Reconnect the connectors, secure the latches, turn on the low and high beams and make sure both headlights are lit. Check that the lights work under vibration. Wiggle the harness to make sure there is no intermittent contact.

Common mistakes and warnings

  • Disconnect the negative battery terminal before working on the wiring. Do not jump power directly without a fuse. This is dangerous because of the fire risk. Driving without lights at night is dangerous. If you cannot find the cause or the wiring is melted along the length of the harness, contact an auto electrician.