Tracing and repairing a faulty heated rear window/heated mirror

[ozfrog]

First thing, I'm not sure where to put this, so it is here in the Peugeot forum because the problem is with my 307. I'm sure that it will be moved to the correct forum by an ever-vigilant moderator.

Neither the driver's side exterior mirror nor the heated rear window of my 307SW are heating. The passenger side exterior mirror is heating. Tracing faults like that are beyond my pay grade, so off to the auto electrician I went last week.

They tested what they needed to and found that power was getting all the way to the mirror and to the heated rear window. But still neither was heating up. They left it at that, suggesting that I get a replacement rear window(!) and a replacement exterior mirror.

When I went to collect the car, they told me that they were not prepared to take off the mirror and risk breaking it because I wouldn't be allowed to drive the car out of their workshop without that mirror, and they were 99% certain that I wouldn't be able to get one that day. They were correct about not being able to get a replacement mirror that day. I haven't found one even 5 days later, despite many being advertised on eBay and Gumtree. However, I don't think they looked very hard to find instructions for removing the mirror because I found a set of text instructions for removing the mirror glass almost immediately after I got home.

When I showed them the removed mirror glass today, they pointed out that one of the connectors was rigid, but the other was floppy. This, they suggested, meant that the connector had probably broken away from the heating wires on the back of the mirror glass.

As far as my skills go, I can't see a way of separating the plastic backing from the mirror itself. The parts book excerpt I've attached shows that Australia gets its own version of the driver's side exterior mirror, but unfortunately, I can't find an image of the reverse of the mirror glass that has the plastic mounting or backing. If anyone has seen the reverse side of the mirror and knows what I'm talking about, I'd be interested to know if you think it is possible for that plastic backing to be removed. Or am I on a wild goose chase?

Now the rear window! Is there an easy method to find which strip across the rear window is broken? None of them appears to be broken with the naked eye, and my eye surgeon said that my vision is as close to 20/2o after my cataract removal!

[mickthemaverick]

This diagram may give you an idea:

https://ultimatestyling.co.uk/peugeot-3 ... -ult432-mg

[PaulC5]

For the rear window it might be more than just a strip that is broken as when I had this it was just the one or 2 strips that did not heat up, not all of it. You could look at each strip shining a torch through but it could be the connector part that needs attention. When they were checking did they check the supply and earth side of it or just for a supply ? It also needs a few amps supply, not just for a voltage or continuity which a part broken wire would pass and appear ok.

[ozfrog]

When they were checking did they check the supply and earth side of it or just for a supply ?

They specifically mentioned that they had tested both sides.

For the rear window it might be more than just a strip that is broken as when I had this it was just the one or 2 strips that did not heat up, not all of it.

I’m no electrician, but doesn’t that depend upon whether the strips (the system) are wired in parallel or in series?

To demonstrate that I’m no electrician, I don’t even know if such a system (a heated window) can be wired in series.

You could look at each strip shining a torch through but it could be the connector part that needs attention.

Does this trick work in the dark only?

Maybe I’m giving them too much credit, but if they tested both sides of the window, surely they would have noticed if the connector(s) were the problem?

It also needs a few amps supply, not just for a voltage or continuity which a part broken wire would pass and appear ok.

Again, maybe I’m giving too much credit to them, but surely they should know something so ‘basic’?