Outside Temp sensor issues

[Mikebmth]

Hi all,

Just bought a new Outside Temp Sensor for my Cav as mine was all over the place, bought a £4 one off of ebay that was claimed to be brand new but have it fitted now and still reading -2 degrees which it definetly aint as the work van says +14 ish..

Is there anything else that goes wrong with these? If I disconnect it then temp display goes to blank so know its getting a signal.

[Hayward691]

Might be inside the display unit... I burnt mine out, then repared it and got some rather off temps...

[A-J]

Try liberating one from a scrap yard, if it has the triangle plug then one off pretty much any vauxhall will fit (I did my mums Agila with one from a 98 vectra )

Always worth trying another sensor to rule it out, especially if it's free

[planetc]

Make sure the connections are clean and tight Mike, it works by measuring the resistance of the sensor, so any crap will mess with the reading.

[suzi]

hi all mines gone doolally readimg 80.00 or -- -- where do i get to replace it or clean it guys
help very much appreciated
thanks

[Robsey]

Okay Suzi,

Go to the uk pasenger side front wheel.
The sensor is mounted through a hole in the bottom of the front bumper.
It will be about 15cm (6") from the rear edge (wheel arch) ofthe bumper.

It is a little black sensor about the size of a fat thimble.
It is held in by three little plastic tangs.
There will be two wires going to it -
A blue one, and another blue one with a white stripe along it.

There are three possible faults with sensors..
A) no reading - sensor not fitted / connected, or corroded broken connector pins or wires.

B) low reading - corroded pins in the connector or internal sensor fault.

C) stupidly high readings - sensor is faulty internally.

[suzi]

Thanks Rob,

One to have a look at probably all 3 knowing my luck are they easy to replace if needed?
If its c: does that mean something in the car its self is wrong?

Cheers suzi

[Robsey]

Hi Suzi,

Yes once you find it, it is a matter of squeezing at least a couple of the plastic tangs in so that the sensor will push up out of the bottom edge of the bumper.

The sensor then just unplugs from the cable / connector.

I assume the "C" that you are getting is simply the symbol for Celsius / Centigrade.

The lack of a number in front of this suggests that there is no sensor connected.
I am also guessing that you have the dual info display.. so temperature in one window and time in the other.

I would expect an "F" to appear in the temperature window, but then it is a long time since I had one of those displays.

Weather permitting, I shall get some pictures tomorrow for the sensor location etc... and what it looks like etc...
Hmm potential How 2 / info-guide perhaps.

[suzi]

Thanks for your reply Rob,

how 2 guide sounds great lol. When i said c, i ment the one you put C) stupidly high readings - sensor is faulty internally.
Yes the reader in car has clock underneith both digital

[Robsey]

Well the weather was pants today, so here are some googled images to get us started...

1) The sensor is located on the UK passenger side of the front bumper.
It is approx 6 inches (15cm) forward of the wheel arch.

cavalier.jpg (42.94 KiB) Viewed 1702 times

2) Locate the sensor on the underside of the bumper -
Squeeze the plastic retainer tangs in, and then push the sensor up out of the bumper skin.

3) The connector sits inside the sensor body...
It has two blue wires going to it
One blue wire and
a blue wire with a white stripe on it.

To release, lift the plastic loop / catch clear from a little retainer tang on the top of the sensor.
Be careful with this, as it is possible to snap the loop off if you are heavy handed / clumsy.
(Especially in very cold conditions, where plastic becomes less flexible / more brittle.)

Once the loop is clear of the retainer tang, pull the connector out of the sensor body.

Then simply plug the connector into a new sensor,
Push the sensor through the hole in the bumper skin.

Job done.

I will do a proper how 2 with pictures from my own Cav in due course...
I will also trace the wiring to the bulk-head, where some (very few) vehicle wiring stops.
(base model vehicles with analogue clock only)

[Robsey]

hi all mines gone doolally reading "80.00" or "-- -- "

Hmm two trains of thought on this.

the 80 suggests that the sensor is tatered...

the -- -- suggests that either the display connector or the sensor connector is faulty / dirty.

I would look at the bumper mounted sensor plug first, as it is exposed to the elements,
The connector pins may be getting wet ( high temperature readings) and there may be some corrosion (-- -- readings).

If this is the case, I would suggest cleaning the pins to shiny metal, drying them, and then pack a little petroleum jelly (vaseline) into the sensor socket, before plugging the connector in.
This should prevent any further corrosion or water ingress.

There is a connector on the bulk-head of the engine bay, roughly in front of where the glove box sits..

as mentioned above look for the two wires ( blue and blue/white) - separate the connector, and treat as I described for the sensor connection and pins.

the only other connector is on the back of the dual info display... .
The checks for this would be that the plug is firmly fitted into the display, and that the same two coloured wires look okay.

That's about as much as you can check..
as suggested above - you could get a sensor from a scrap vauxhall of virtually any age... there are two types, but they all seem to fit and work the same.

[suzi]

Hi Rob,
Thanks ever so much looks pretty easy I will defo have a go at weekend if its not raining, if its faulty would any Vauxhall fit say frm astra or vectra

Thanks once again
Suzi

[Robsey]

I could check the vauxhall epc for you (computer based parts catalogue).

But I have used Corsa, Astra, Omega senders successfully.
Cannot see a problem with Vectra B etc.....

[suzi]

Cheers rob

[Robsey]

Okay there are indeed two sensors
90 477 289 which covers-
C89 - Calibra
J89 - Cavalier mk 3 / Vectra A
J96 - Vectra B
S93 - Corsa B & Tigra A
V94 - Omega B

This was then superceeded by
9 152 245 which covers all those already listed plus -
H00 - Agila
A04 - Astra H
T92 - Astra F / mk 3
T98 - Astra G & Zafira A
P10 - Astra J
X01 - Corsa C
S07 - Corsa D
U99 - Frontera B
G09 - Insignia
X03 - Meriva
Z03 - Signum
Z02 - Vectra C
X04 - Tigra B
X83 - Vivaro
A05 - Zafira B

So yup, more or less any Vauxhall / Opel.

[suzi]

Thanks could nick my dad off mariva lol but don't think he'd be too pleased

Thanks once again Rob

Suzi

[saucy_begger]

dont buy anything like that off ebay. i had the same problem with my sensor so i bought one off ebay and still had the problem so bought a new display and still had the problem so went to vauxhall and bought a new sensor for about £9 and it works perfectly now.

the add for the sensor on ebay said new on the one i got. they are crap.

[suzi]

Thanks was thinking scrap yard but if the that cheap will goto Vauxhall.

Cheers suzi