1991 XJS 4.0 - Engine Management Code FF14

[nick471517]

Just purchased a 1991 XJS 4.0L - on first long run the 'check engine' warning light has come on - code FF14 - can anyone shed any light on what this means - any help much appreciated.

[MARKPEARSON]

Hello nick
FF 14 refers to coolant thermistor or associated wiring.
Looks for coolant thermistor static during engine warm up,
The sensor is located on top of thermostat housing.
This is a temperature sensetive resistor. The resistance decreaces with
an increasing engine tempertature.
Easy test is to pull plug off sensor then start engine and with multimeter
measure resistance across the two pin connections and watch for resistance to decreace no change means temp sensor faulty.If it decreaces you will need to physicaly inspect wiring harness and associated plugs,but in my opinion it will most likley be the sensor.
The sensor part no is DBC3728 they cost £13.01 from jaguar dealer.
Hope this helps
Regards Mark (93, 4.0)

[nick471517]

Thanks Mark - much appreciated