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Hi, I own a vento and suddenly my trunk open light is not working. The bulb is okay but it is not lighting up. I have used different bulbs also. The socket wire is good, I can see voltage at it. But when bulb is connected, trunk open warning light is not showing. When bulb is disconnected, trunk open light is showing in dashboard.

I checked online and see that the switch in latch is bad, but if that was the case the indicator would not show. I checked current flow diagram but I don’t understand how is the bulb circuit connected is so unfortunately I’m stuck. If anybody else has faced this issue please do let me know. Thanks in advance.

i think it is due to broken latch micro switch.
Vw seems to have issues with micro switches, i wish they made it easily serviceable, but they like their euros

You also have a diode where you put the bulb, bud i doubt it failed. You can check it

So at the trunk light you have 12v at the connector ? The micro switch sends the negative/ earth side to switch the light on.
With the bulb out there is no load on the circuit this maybe why the dash light works , please check the wiring in the trunk lid hinge area first , you may have a broken wire or a damaged wire .

amer6R wrote: ↑Sun Dec 31, 2023 5:10 pm i think it is due to broken latch micro switch.
Vw seems to have issues with micro switches, i wish they made it easily serviceable, but they like their euros

You also have a diode where you put the bulb, bud i doubt it failed. You can check it

I too thought the same, even replaced the diode it didn’t work.

CarbonChaos wrote: ↑Mon Jan 01, 2024 8:27 pm So at the trunk light you have 12v at the connector ? The micro switch sends the negative/ earth side to switch the light on.
With the bulb out there is no load on the circuit this maybe why the dash light works , please check the wiring in the trunk lid hinge area first , you may have a broken wire or a damaged wire .

Yes there’s 12v at the connector. Thanks for the info, I’ll check the wires. I should have continuity from the negative side to ground when the trunk is open, right?