Boot won't open, can someone help me troubleshoot?

[GolfVFSI]

Hi all,

Could use some help to troubleshoot what's preventing my boot from unlocking/opening.

I removed the boot plastic cover and after having a look at the system:

- VW logo doubles doubles down as a switch. When I push the VW logo, the white bite rotates and activates the switch. I can hear a "click" when I push the logo down



- Then the switch mush send a signal to the boot lock latch pictured below for the latch to disengage.



What would be the best way to proceed to figure out which part is the culprit here?

Any help/insight would be appreciated

[Supramonsta]

Just a note, I purchased a mk5 and the fix applied from a very mechanically minded previous owner was to leave the trim off and tied a cord around the latch so you have to drop the back seat, lean in and pull it. It obviously had him stumped too, although mine is intermittent.

[JustCruisn]

Either that switch is stuffed, broken wire or the lock is dead.
I had broken wires in a Jetta boot and also an SL350 Merc. the harness flexes when the boot opens. broken wires in the harness. Easy enough to fix.

You can check the switch, look for continuity on the switch pressed vs not.

Very common for bad door locks, based on my experience with Mk4 & 5 platform.

[h100vw]

That has been repaired before at VW. See the yellow wires. I'd open up th eloom and have a look in there for a broek wire.

[Guest001]

You can buy a new lock for about $25 on ALI express and just about all models use the same one.

https://www.aliexpress.com/w/wholesale-boot-lock-vw-polo.html?spm=a2g0o.home.auto_suggest.10.187176dbF U4FW9

https://www.aliexpress.com/item/1005...Cquery_from%3A

[GolfVFSI]

Sorry guys for the late reply. Life happened and couldn't get around to fixing this but now I've got time to look into it.

Either that switch is stuffed, broken wire or the lock is dead.
I had broken wires in a Jetta boot and also an SL350 Merc. the harness flexes when the boot opens. broken wires in the harness. Easy enough to fix.

You can check the switch, look for continuity on the switch pressed vs not.

Very common for bad door locks, based on my experience with Mk4 & 5 platform.

I bought a new lock off ebay and replaced it but doesn't work so we can rule out the lock.

I'd like to test continuity. Are you able to tell me which pin/wire on both sides (lock and switch) I need to probe?

That has been repaired before at VW. See the yellow wires. I'd open up th eloom and have a look in there for a broek wire.

How can you tell it's been repaired? What about the yellow wire?
Just to confirm, to check the wires I need to open the black harness wrapped around the wires correct?

[JustCruisn]

VW repair wires are yellow. Originals would have had different colour codes on each wire.
One way is to use a multimeter to check the wires, you also need to know where they run to but since the colours have changed to yellow this is gonna be hard.

I'll wager a beer that there is a broken wire in the hinge area at the top of the door near the roof, where the harness moves, probably inside a rubber boot.
You need to open the wiring harness, remove the black tape and check the wires for a break. Patch the wire, test and then wrap the harness using a decent fabric loom tape, not PVC electrical tape.
Disconnect the battery when you are working on it.

[GolfVFSI]

- That's the hinge area you are speaking of right? If yes, I'll remove the boot and inspect the wires.




- Re multimeter to check the wires (continuity). Correct me if my reasoning is wrong. Don't know where the wires run to because colours have changed as you said, but I just realised that there isn't that many possible combinations anyway.
The switch/VW emblem connector has two wires, 1 and 2 and the lock connector has 4, ABCD as highlighted below
SO what I did is put the black probe to 1 and red probe to A, B, C and D one by one and look for a reading. Repeat for the 2nd switch/VW connector. Though the reading stayed at 1 for all combinations, unsure if I should have activated the switch? (couldn't push the VW emblem)



- Also last question, had an idea earlier to rule out the switch/VW emblem as faulty. Below in the pic is the switch connector. Is there a way to measure if there's a signal that comes out of one of those wire? If yes, how to set up my multimeter, am I looking for a voltage, Amps or resistance?



If we can measure the signal, that would confirm whether the switch is faulty or not. If not, it would mean it's a broken wire because I already swapped the lock and it's not that

[GolfVFSI]

So I was told I could check if the switch/VW emblem worked by testing for continuity and touching both leads of the connector (last photo on my previous post above)

When the switch is activated (VW emblem pressed) the resistance goes to 0, when switch off meters read 1. Repeated multiple times and each time switch is activated I have a reading of 0.

So from my understanding, this means the switch works right?

Which would mean the issue is a broken wire. I'll inspect the hinge this weekend and hopefully I find a broken wire

[JustCruisn]

Yep the boot in the pic is where you should start looking.
Test on the switch was correct also.