Jaguar Repair: 1984 XJ6 heat, intermittent operation, foreign cars

Question
Howard,
The Tennessee summer heat has ended abruptly, which causes me to begin pondering the interior heating in my XJ6. I understand that I have two blower motors, but it seems I do not always have both operating. My luck, it is the left blower that seems to be off and on. In your experience, is such intermittent operation of blower motors an indication of a failing motor, or as simple as loose wiring? I haven't dug in yet to investigate, I like to ask for a little direction first. Also, I do not seem to get more than a gentle breeze from the center high vent, even on "high". Is this normal? I am used to a more robust air flow from other foreign cars of this vintage.
Thanks,
Michael

Answer
Hi Michael,
I found that it is a waste of time trying to guess or diagnose by symptoms. The ONLY way to correct a problem is to test (at the time of failure)

You already know what is failing so all you need to do is to test while it is in a failed mode. If you don't have a wiring diagram let me know and I will put one on my web site for you to copy.

Howard