405 GTX thermometer

eye_flys · Unread post by **eye_flys** » 14 Dec 2008, 20:07

I recently bought a 405 GTX TD estate, seems to be a pretty honest and tidy example. I got the clutch and wishbone bushes replaced and it's driving bob-on now. I intend to get it up to scratch within the next few months and keep it for a long time.
I replaced the bulbs in the clock/thermometer display so it isn't invisible to the human eye anymore
Anyway, the thermometer isn't working. I plugged it in and it read the correct outside temperature, then rocketed up to 70C in 3 degree increments. Now it just flashes "--C". Should I be looking at replacing the display, or the sensor on the mirror?
I only ask because it's a handy feature to have at this time of year.

Unread post by **CitroJim** » 15 Dec 2008, 18:28

The "---C" indication is often given when the sensor dies. Have a check of the connector plug just downwind of the mirror. It's not exactly waterproof in the vicinity and it only take a bit of corrosion on the pins to upset the tiny current that flows in the sensor. It's just a little bead thermistor.

steelcityuk · Unread post by **steelcityuk** » 15 Dec 2008, 21:08

I had a 405 GTX TD Estate. Was a lovely car, N reg with just 91K with full service history. Comfortable and very practical, loved it's looks too in dark metallic blue. Then some pillock in a white Astravan shoved a car into the rear and wrote it off. I got paid out the same as I paid for for it and so I bought it back for peanuts, swapped the back door, had it tested and checked at VOSA depot and passed it on to the wife. She did nothing but moan about how big it was and that she wanted another VW Polo (she had one before I gave her the 405) because 'they're so much better built'. So I sold the 405 she bought another Polo and it's nothing but trouble, it's rusting, the rear wiper stopped working, the CAT failed, broken spring, etc. etc.

Steve.

eye_flys · Unread post by **eye_flys** » 23 Dec 2008, 19:18

citrojim wrote:The "---C" indication is often given when the sensor dies. Have a check of the connector plug just downwind of the mirror. It's not exactly waterproof in the vicinity and it only take a bit of corrosion on the pins to upset the tiny current that flows in the sensor. It's just a little bead thermistor.

ta for the info. Where is the connector plug exactly? I did take the mirror off but couldn't find it.

steelcityuk - I had a VW Golf 1.9D 2 cars ago and it was horrible - uncomfortable, rusty, cheaply and badly-engineered in places. The only redeeming factor was the very hard-wearing engine. People just buy the things on strength of the badge and marketing.
This is my second 405, my last one gave me no troubles and I don't expect this one to either!

r.welfare · Unread post by **r.welfare** » 03 Jan 2009, 17:15

Connector plug will be clipped to the inside of the door - about an inch down from the start of the door trim IIRC. Take the door trim off as well as the interior mirror blanking plate thing and you should be able to find it. There will be two cables and connectors - one for the mirror switch and a smaller one for the temp connector.