diagnosing air conditioning - Defender Source
Defender Source  

Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions

Join the Defender Source Community Today
Reply
 
Thread Tools
  #1  
Old July 7th, 2014, 08:29 AM
rankar's Avatar
rankar
Status: Offline
Randy
97 SW #2236 (Maggie)
Member
 
Join Date: Aug 2013
Location: CT
Posts: 1,115
Registry
diagnosing air conditioning

I did a search for a thread on this but couldn't find one. If you know of one, please let me know...

I could use some advice with diagnosing an a/c issue. It was working fine, blowing cold, and now all of a sudden I don't even hear the fan going. Checked the fuse as usual, nothing there.

So where do you recommend I go next? Fan relay? Something else?

Thanks guys
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old July 7th, 2014, 08:48 AM
roverman2010's Avatar
roverman2010
Status: Offline
John
1985 LR 90 200Tdi
Member
 
Join Date: Sep 2011
Location: Galveston Island, NearTexas
Posts: 2,043
Registry
Find the low pressure valve/switch on the low pressure piping and use a paper clip or something like that and jump the terminals, if AC starts up you have low gas pressure. That's the first thing I check, easy first step, you can also check you have power or not at the compressor clutch, use that 12 volt test lamp that everybody has in their tool box?
__________________
Edward Teach is the Blackbeard, and is a member of the Birmabright Brotherhood.

Still looking for that place where I can carry a paddle and get asked what's that.

JnK Services
FC101 GS FFR
57 LR 88" SXF 858
85 LR90
95 D1 Tdi
05 D3 HSE
97 XK8 FHC
Reply With Quote
Sponsored Links
Advertisement
 
  #3  
Old July 7th, 2014, 08:54 AM
evilfij's Avatar
evilfij
Status: Offline
evilfij
I have never seen a rover in person
Member
 
Join Date: Oct 2003
Location: on the internet
Posts: 14,653
Quote:
Originally Posted by roverman2010 View Post
Find the low pressure valve/switch on the low pressure piping and use a paper clip or something like that and jump the terminals, if AC starts up you have low gas pressure. That's the first thing I check, easy first step, you can also check you have power or not at the compressor clutch, use that 12 volt test lamp that everybody has in their tool box?
That wont stop the fan from blowing.
__________________
*not legal advice*
Reply With Quote
Sponsored Links
Advertisement
 
  #4  
Old July 7th, 2014, 09:04 AM
roverman2010's Avatar
roverman2010
Status: Offline
John
1985 LR 90 200Tdi
Member
 
Join Date: Sep 2011
Location: Galveston Island, NearTexas
Posts: 2,043
Registry
Depends which fan he is talking about?
__________________
Edward Teach is the Blackbeard, and is a member of the Birmabright Brotherhood.

Still looking for that place where I can carry a paddle and get asked what's that.

JnK Services
FC101 GS FFR
57 LR 88" SXF 858
85 LR90
95 D1 Tdi
05 D3 HSE
97 XK8 FHC
Reply With Quote
  #5  
Old July 7th, 2014, 09:06 AM
JFD's Avatar
JFD
Status: Offline
Julien Dalbin
05 Tdi 90
Member
 
Join Date: Mar 2005
Location: Dominican Republic
Posts: 1,888
Fan speed selector resistance or whatever this is called.
They burn all the time, but generally not all the speed at once.
Blower relay also but they generally don't give troubles.
__________________
" Eventually everything connects - people, ideas, objects. The quality of the connections is the key to quality per se. "
- Charles Eames
Reply With Quote
  #6  
Old July 7th, 2014, 09:07 AM
Overlander's Avatar
Overlander
Status: Offline
mark kellgren
93' NAS 110- #234
Member
 
Join Date: Mar 2006
Location: Charlotte, NC
Posts: 6,514
Registry
I have had trouble in the past with the main ground connection in the big brown multi-wire connector to the right of center on the A/C facia. It's one of the main harness connections. when I was having trouble, tapping that brown connection would cause it to start again (fan and a/c). Sometimes that brown connector would get so hot I couldn't touch it. All these issues were do to that unreliable ground connector.

I ended up pulling main ground (10awg) from both sides of the connector and using blade connections to join them directly instead. Not a single issue since.
__________________
Mark Kellgren
KM4BOR

ISIL and al qaeda can go F*ck themselves...
Reply With Quote
  #7  
Old July 7th, 2014, 10:30 AM
rankar's Avatar
rankar
Status: Offline
Randy
97 SW #2236 (Maggie)
Member
 
Join Date: Aug 2013
Location: CT
Posts: 1,115
Registry
Thanks guys for the info. Just to clarify, it is the fan speed selector. Turning the selector to any of the fan speeds does not turn the fan on, but I do hear what I believe is the compressor turning on.

Let me know if this triggers any more ideas. In the meantime, I'll get going with doing tests on the ground wire, switch, and relay.
Reply With Quote
  #8  
Old July 7th, 2014, 10:36 AM
tjfslaughter's Avatar
tjfslaughter
Status: Offline
thomas
Burbon
Member
 
Join Date: Feb 2010
Location: NorthEast
Posts: 4,456
I am willing to bet the fan switch is toast. You should be able to hard wire it to test it after you ensure it is grounded.
__________________
Reply With Quote
  #9  
Old July 7th, 2014, 11:04 AM
Jymmiejamz's Avatar
Jymmiejamz
Status: Offline
Jimmy
1995 D90 SW #365
Member
 
Join Date: Sep 2010
Location: Brooklyn, NY
Posts: 3,465
Registry
Quote:
Originally Posted by roverman2010 View Post
Depends which fan he is talking about?
The condenser fan will also run without any refrigerant in the system.
__________________
Car Camping Collective founding member and Treasurer
Reply With Quote
  #10  
Old July 10th, 2014, 06:04 PM
rankar's Avatar
rankar
Status: Offline
Randy
97 SW #2236 (Maggie)
Member
 
Join Date: Aug 2013
Location: CT
Posts: 1,115
Registry
Just an update here... so I pulled out the a/c fascia and got access to the relay and switch.

1. I jumped the wires in the blower multi-switch (positions 5 and 2, brown and green) and no blower
2. I measured the voltage across the short I created and I'm getting 12V (but my ground lead was connected to the chassis)

So I'll try Mark's suggestion next to check the multi-connector ground.

So it seems like the relay is intact and the multi-connector to the blower switch is providing ample power.

If it's not the ground, do you think it's narrowing down to the blower itself?
Reply With Quote
  #11  
Old July 13th, 2014, 07:58 AM
rankar's Avatar
rankar
Status: Offline
Randy
97 SW #2236 (Maggie)
Member
 
Join Date: Aug 2013
Location: CT
Posts: 1,115
Registry
Ok all fixed. Damn ground wire to the blower. I went looking around there with my inspection mirror, tugged on the ground very lightly and saw this... (thanks guys for all your help) Click image for larger version

Name:	uploadfromtaptalk1405256272767.jpg
Views:	175
Size:	66.7 KB
ID:	98695
Reply With Quote
  #12  
Old June 22nd, 2015, 02:36 PM
Anschluss
Status: Offline
T B
white 1997 Defender 90 NAS
Member
 
Join Date: Jan 2013
Location: Woodstock, Ontario
Posts: 37
I have just had a similar experience with my 97 D90. AC fan started to cut out intermittently and finally didn't blow at all. Thought I could hear the compresser kick in but no fan. As mentioned above, it was a loose wire underneath. Simple.

Hey... thanks to all of you amazing people who take the time to help point people like me in the right direction.
Reply With Quote
  #13  
Old July 10th, 2015, 12:37 PM
bomilcar's Avatar
bomilcar
Status: Offline
Stephen Miller
73 Series III Orig Owner
Member
 
Join Date: May 2006
Location: Cerrillos, New Mexico, NM
Posts: 74
AC switches

Any one know where I can track down replacement switches for my 1994 Defender AC unit? Both temp and blower? Grounds are good but it seems that the blower switch is intermittent. I tried the obvious sources with no good fortune.
Thanks,
Steve
__________________
Steve
73 Series III (Original Owner)
94 D-90
2011 LR4

"anything that can go wrong has"
Reply With Quote
  #14  
Old July 10th, 2015, 12:48 PM
phoenix37's Avatar
phoenix37
Status: Offline
john
97 D90 ST / 1957 S1 109/ 1983 LS110
Member
 
Join Date: Feb 2008
Location: Venice, CA/Yarmouth,ME
Posts: 5,020
Registry
might want to ask these guys if they have something that would work.

Old Air Products - Home of the HURRICANE Heat, Cool, & Defrost A/C System - Underdash Pod
Reply With Quote
  #15  
Old June 21st, 2016, 08:42 AM
bomilcar's Avatar
bomilcar
Status: Offline
Stephen Miller
73 Series III Orig Owner
Member
 
Join Date: May 2006
Location: Cerrillos, New Mexico, NM
Posts: 74
AC Pressure switch

More AC problems. 1994 D-90. Turned the AC on for the summer and it worked great for about 15 min and then shut down. Was scheduled to take it to my local dealer to change out the radiator and add duel electric fans. Added the AC problem to the service list. After some trouble shooting it was decided the culprit is the pressure switch (two lead). Turns out as expected the switch is no longer made. Checked with the usual mail order suspects with no luck.

Any thoughts or ideas would be greatly appreciated
__________________
Steve
73 Series III (Original Owner)
94 D-90
2011 LR4

"anything that can go wrong has"
Reply With Quote
  #16  
Old August 22nd, 2016, 09:15 AM
bomilcar's Avatar
bomilcar
Status: Offline
Stephen Miller
73 Series III Orig Owner
Member
 
Join Date: May 2006
Location: Cerrillos, New Mexico, NM
Posts: 74
I am still trying to track down an two lead AC pressure switch for my 94 Defender. Dealer has been unsuccessful. Tried Rovers north and BP.

Any one know an after market part number or have a suggestion on tracking one down?
Thanks.,
__________________
Steve
73 Series III (Original Owner)
94 D-90
2011 LR4

"anything that can go wrong has"
Reply With Quote
  #17  
Old August 22nd, 2016, 09:32 AM
Uncle Douglas's Avatar
Uncle Douglas
Status: Offline
Doug Crowther
A defender in every driveway-motto
D-90 Source Vendor
 
Join Date: Dec 2007
Location: Gods Country- Central Virginia
Posts: 11,364
Registry
Quote:
Originally Posted by bomilcar View Post
I am still trying to track down an two lead AC pressure switch for my 94 Defender. Dealer has been unsuccessful. Tried Rovers north and BP.

Any one know an after market part number or have a suggestion on tracking one down?
Thanks.,
Pressure switches are generic. Remove it and figure out what thread it is and finding one should be easy.

That said its easy to bypass one with a jumper wire. They are there to protect your compressor but when the switch is whats bad and you know the system is charged correctly, I bypass them in the interest of comfort until a replacement can be sourced.
__________________
Good judgement comes from experience,experience comes from bad judgement.

Dividing Creek Imports
Worldwide Land Rover Shipment and Importation Service
Bespoke Restoration & Modification work


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

410.693.1391


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote
  #18  
Old August 22nd, 2016, 09:52 AM
bomilcar's Avatar
bomilcar
Status: Offline
Stephen Miller
73 Series III Orig Owner
Member
 
Join Date: May 2006
Location: Cerrillos, New Mexico, NM
Posts: 74
Thank you Sir!
__________________
Steve
73 Series III (Original Owner)
94 D-90
2011 LR4

"anything that can go wrong has"
Reply With Quote
Sponsored Links
Advertisement
 
Reply

Lower Navigation
Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Help Diagnosing a winch problem... bharris Defender Technical Discussions 8 April 28th, 2010 04:19 PM
Need Help Diagnosing Odd Sound fleabus Defender Technical Discussions 6 November 22nd, 2009 10:16 PM
Diagnosing Fuel Pump Issues hutch Defender Technical Discussions 40 May 21st, 2009 08:04 PM
Diagnosing D110 Climate Controls 61rover Defender Technical Discussions 6 September 27th, 2007 11:13 AM
Need help diagnosing electrical issue cgalpin Defender Technical Discussions 22 January 25th, 2007 07:53 PM


All times are GMT -5. The time now is 03:21 AM.


Copyright