Cooling Fans come on stay on

95 XJ6/w 4.0 liter motor: I rarely use my AC but when I did it created an issue. The cooling fans stay running until the battery is dead. I disconnected the wiring on the firewall waited and reconnected days later and they came on right away with the car not running. I looked for a relay up front behind the headlight, there were 3. I tried disconnecting each of them and nothing happened. Is there another area it could be located? Luckily the temps are dropping and the fans rarely ran except on hot summer days so running sans fans and AC isn’t a problem right now.
Ideas from the brain trust??

What year car do you have will help

and engine

95 with a 4 liter , just added that thanks…

Jaguar issued several TSBs for the cooling fans

14-04 Cooling System – Fan Fuse Failure.pdf (39.4 KB) 14-06 Cooling System Fan Fuse Failure.pdf (39.5 KB)

Make sure you understand how the system operates.

It stopped raining for a minute so I went and looked at the connections. Appears they did service on it, just one switch and the white wire harness is jumped.

If I reconnect the other harness the high speed fans come on and stay on. Both fuses were good.



That is correct it’s to prevent surges blowing the fuse I always used to unplug that in winter to allow the fans to operate as designed try that, they should be switched on by the trinary switch IIRC and mine never blew a fuse if I forgot to reconnect that.
Give it a try

If you connect the trinary switch without the A/C compressor operating and the fans immediately jump to high speed, then the switch is FAULTY!!!


I’ll give that a go tomorrow. Then onto repairing the aux water pump for the heat, gonna need that soon… :slight_smile:

Hey Bob,
Off hand do you know if that switch is threaded into a Schrader type valve or do I lose freon in the replacement? I’d assume on a car of this caliber for the time they would have a valve…

Noticed your avatar, you shooting that old revolver? Just picked up a new 1911 style Walther .22 for plinking.



The REALLY early cars did NOT have Schrader valves.

From TSB 14-02 dated 10-04

The refrigerant liquid lines of 1995 MY Sedan Range vehicles from VIN 720580 have Schrader
valves in the fittings for the dual (binary) and triple (trinary) pressure cutout switches. The Schrader
valves allow the switches to be removed without depressurizing the system. No Schrader valves
are fitted to 1995 Sedan Range vehicles from VIN 720001 - 720579.

The entire TSB is here.

14-02 Air Conditioning Pressure Switches.pdf (26.5 KB)

Yes I shoot the Webleys (I have a MK II and a MK VI) I also have an old S&W first model Frontier DA 44 (cir. 1886) that I load black powder ammo for. Cap and Ball revolvers also interest me as my Granny gave me an old 1851 Colt Navy cir. 1860.


Woot, 743174.
Pretty cool firing a gun from that era.
There were a couple black powder guys at the range last weekend. Talk about the fog of war, the two of them created quite a cloud. :slight_smile:

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