Topic: Outside temperature gone bonkers (Read 1883 times)

JasonH · « **on:** 16 December 2010, 17:08:24 »

My (facelift) 2.5V6 recently started declaring the outside temperature was 33C (when it was around 0C outside), it then started drifting around down to -40C, now it's pot luck what it reads. Today hit +12C and -37C!!!

I would have considered ignoring it but my climate control takes heed of this. So it's -5C outside but the sensor says 33C, Mr Climate Control says oh no you can't have warm air inside it's way too hot for that....

I found the sensor, actually hanging loose, behind the washer bottle behind the front bumper.

I ordered a replacement, it turned up, and I fitted it. No change - b*gger. In fact no sensor at all does exactly the same.

I'd expect no sensor to flag an error or hit a hard -40C and stay there.

So any suggestions on what's going on. Is there yet another temperature sensor somewhere (I know there's an air intake temperature sensor and at least two coolant temperature sensors)?

freecall666 · « **Reply #1 on:** 16 December 2010, 18:07:53 »

check the wire's and the plug connection, if been hanging around may have damage the wiring.

JasonH · « **Reply #2 on:** 16 December 2010, 20:25:06 »

The wiring looks fine, but I've not put a voltmeter across it yet (mainly because I haven't figured out what voltage I'd be looking for).

However, I think the new sensor may actually be fine. It's just taken a little while to average out the bonkers readings. It seemed to be reading correctly on the way home tonight.

I'll check again tomorrow.

JasonH · « **Reply #3 on:** 30 December 2010, 12:28:33 »

All solved, but useful for others to know the cause.

It wasn't the sensor, so I replaced that unnecessarily.

On the facelift the sensor is in the middle, under the washer bottle. I checked the connector and it was fine. I'd replaced the sensor and it was much the same as before.

Checking the wiring diagrams it seems that essentially the two wires go straight into the MID so there isn't much to go wrong.....

The wiring from the sensor disappeared into the loom.

So what could go wrong?

Turns out there's another connector, just under the front bumper near the horns. Reached underneath, unclipped it and found it full of rusty water....

Squirted both sides with WD40, reconnected it and bingo sensor reads spot on - exactly the same as my other car. Hooray, my climate control works again

Kneepad · « **Reply #4 on:** 30 December 2010, 13:05:23 »

Cheers Jason, useful piece of information. Good detective work on your part.

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Author Topic: Outside temperature gone bonkers (Read 1883 times)

JasonH

Outside temperature gone bonkers

freecall666

Re: Outside temperature gone bonkers

JasonH

Re: Outside temperature gone bonkers

JasonH

Re: Outside temperature gone bonkers

Kneepad

Re: Outside temperature gone bonkers