External air temp sensor fell off

zony · 4th February 2017, 18:18

I removed the undertray last week when I replaced the alternator, I left it off as I was changing the oil this weekend. It was too wet to do it all in one go. At work during the week I noticed something hanging down at the front of the car. Yes you've guessed it, temp sensor missing and -30 degrees on the dash.

I bought a new A/C automatic sensor from eBay but now shows -27.5 degrees. Either I have bought the wrong thing or it's a duff non OE unit. The connector was a little damaged on the edge but nothing major. What is the correct part I need please.

stevestrat · 4th February 2017, 18:20

Don't panic! If the external temp sensor is disconnected/replaced it usually takes a few days to get a grip in reality and show a normal reading.

Phil-T4 · 4th February 2017, 19:37

Quickest way to reset it back to normal is to disconnect the battery.

bl52krz · 4th February 2017, 19:45

Hi Phil. Won't just removing it from the connector do the same thing? Especially as he might not have code for radio.

Phil-T4 · 4th February 2017, 19:49

No, that wont do it, power needs to be removed from the IPK so it resets, never tried option 21 on the ipk diags, this may do it.

trikey · 4th February 2017, 19:49

I have genuine sensors in stock should you need a new one.

bl52krz · 4th February 2017, 20:28

Thanks for the info Phil. I live and learn every day.

RPWC · 4th February 2017, 20:32

Mine has not been disconnected, but it was giving strange readings last week, seems ok now though.

Muttley · 6th February 2017, 08:01

Hi guys, my first post!

My external temp is indicating 50 degrees (as I am scraping the ice off the screen), and has been showing that for the last three days (or at least as long as I have had the car!) any ideas?

Phil-T4 · 6th February 2017, 08:04

Its faulty or you have a short in the wiring.

4th February 2017, 18:18	#1
zony Regular poster MG ZT-T Join Date: May 2011 Location: Gellilydan Posts: 48 Thanks: 22 Thanked 5 Times in 4 Posts	External air temp sensor fell off I removed the undertray last week when I replaced the alternator, I left it off as I was changing the oil this weekend. It was too wet to do it all in one go. At work during the week I noticed something hanging down at the front of the car. Yes you've guessed it, temp sensor missing and -30 degrees on the dash. I bought a new A/C automatic sensor from eBay but now shows -27.5 degrees. Either I have bought the wrong thing or it's a duff non OE unit. The connector was a little damaged on the edge but nothing major. What is the correct part I need please.

4th February 2017, 18:20	#2
stevestrat This is my second home ZT260 #243 (resting) Join Date: May 2010 Location: Prestonpans Posts: 22,581 Thanks: 650 Thanked 4,624 Times in 3,358 Posts	Don't panic! If the external temp sensor is disconnected/replaced it usually takes a few days to get a grip in reality and show a normal reading. __________________ Steve T4 Location Map

4th February 2017, 19:45	#4
bl52krz This is my second home Rover 75 cdt club + Rover 2.5 KV6 Conni SE Join Date: May 2008 Location: Birmingham Posts: 11,433 Thanks: 6,587 Thanked 2,262 Times in 1,729 Posts	Hi Phil. Won't just removing it from the connector do the same thing? Especially as he might not have code for radio. __________________ Great Barr, Birmingham.

4th February 2017, 19:49	#6
trikey Premium Trader Rover 75 Join Date: Nov 2010 Location: Devon Posts: 33,818 Thanks: 8,837 Thanked 14,831 Times in 8,030 Posts	I have genuine sensors in stock should you need a new one. __________________ Lest we forget..

4th February 2017, 20:28	#7
bl52krz This is my second home Rover 75 cdt club + Rover 2.5 KV6 Conni SE Join Date: May 2008 Location: Birmingham Posts: 11,433 Thanks: 6,587 Thanked 2,262 Times in 1,729 Posts	Thanks for the info Phil. I live and learn every day. __________________ Great Barr, Birmingham.

4th February 2017, 19:37	#3
Phil-T4 I really should get out more....... MG ZT-T, Rover 75 Tourer Join Date: Mar 2011 Location: Olney Posts: 2,969 Thanks: 245 Thanked 1,088 Times in 657 Posts	Quickest way to reset it back to normal is to disconnect the battery.

4th February 2017, 20:32	#8
RPWC This is my second home 75 model car Join Date: Apr 2011 Location: Newcastle upon Tyne Posts: 20,196 Thanks: 4,008 Thanked 5,083 Times in 3,114 Posts	Mine has not been disconnected, but it was giving strange readings last week, seems ok now though. __________________ Cheers. Rich…

6th February 2017, 08:01	#9
Muttley Regular poster MG ZT 190+ Join Date: Jan 2017 Location: DERBY Posts: 95 Thanks: 56 Thanked 19 Times in 14 Posts	Hi guys, my first post! My external temp is indicating 50 degrees (as I am scraping the ice off the screen), and has been showing that for the last three days (or at least as long as I have had the car!) any ideas?

6th February 2017, 08:04	#10
Phil-T4 I really should get out more....... MG ZT-T, Rover 75 Tourer Join Date: Mar 2011 Location: Olney Posts: 2,969 Thanks: 245 Thanked 1,088 Times in 657 Posts	Its faulty or you have a short in the wiring.