I drove my 1983 XJ6VP today after a long storage. When I turn the climate control to “high”, I am getting the same fan speed as “auto”. Shouldn’t the system on “high” have a faster fan speed? If yes, is the problem likely the resistor pack? The servo/amp seem to be working fine (as I can hear the servo moving from “cool” to “heat” and vice versa).
Originally ‘yes’, Richard, but some were modified ex-factory (or by POs) to do just that.
The blue ‘auto high’ wire from the relay bank was connected to the green/slate wire from the ‘Hi’ speed relay in the bank either at the relay bank or the resistor pack - bypassing the resistors. This gives the same fan speeds whichever of the two relays are activated. Apart from that there are no differences.
It was done for better air flow in ‘Auto’, but is easily reversed - if desired.