Good morning everyone, I have a US spec 1970 LHD XJ. I've done a lot of work to the car over the last year and a half and am very close to getting on the road. One of my biggest challenges is to get my wiper motor to not blow fuses. The motor works while outside the car, plugged into the harness in my hands, however it shoirts when it makes contact with the car. I thought it would be best to check the other items connected to the same fuse. My heater fans have never worked, and I have bypassed them to deal with bigger issues. The wiring in the bulkhead is poor, I have repaired broken and cracked terminals, etc. I have studied the diagram and I simply don't understand how the heater fan resistors are supposed to be wired. They are not referenced by this on the diagram. I am also unsure if there is a relay missing or if the blank location pictured is where the original washer pump was located. I appreciate any assistance you may be able to offer.

Jon

 

J,
is the car fitted with air con? the diagram you are looking at is for air con system, check the diagram on that file page 6 non air con unit next to wiper motor, i see some badly burnt wiring there near the resistors & up on the top right a lot of melted connection so best to expose all that & repair as needed, have you tested the fan motors (disconnected form everything) with direct power? for the air con diagram you are looking at, remove the resistors so you can match the wiring connections as per diagram, the brown wiring from the main terminal to relays will help find the relays, sometimes it's easier to work backwards as in from the motors to the switch

 

XJ Tom, thank you for taking the time to assist me. One of the previous owners decided it would be wise to spray the engine bay in rubberized coating! I have spent considerable time
cleaning wires, contacts and repairing broken terminals. The car is fitted with AC, I am not too worried about getting that working, at least for now. The fans work when tested individually. My thought is that the wiper motor is blowing fuses due to not being connected to the resistors or a relay. Should there be a wiper relay somewhere? I know that the wiper and fans are both connected to fuse number 3.. I will review the file you mentioned, I don't see any resistors mentioned in the original factory wiring diagram.

Jon

 

Jon,
there's no relay in the s1 wiper system that i know of, the system diagram on page 6 of that file shows a basic system, the windscreen washer switch gets power from #3 as well, if the motor works ok off the body work but blows a fuse when in contact with the body then it implies there's an internal cross between pos & neg, have you had the motor apart even just to check the condition of the brushes & clean the armature?

 

Thank you for your assistance! I certainly had a voltage leak as yourself and another Jaguar friend suggested. The issue appears to have cone from the plastic sliding box that connects to the harness. This motor is a replacement, from a slightly later car. My original wiper motor had rusted badly, damaging the armature. I had discarded this some time ago, but kept the body and all the other parts from it. I spent a few hours last night taking the two and building one good motor. I chose to use the body of the original as the sliding connector was much sturdier. Unfortunately the two units are not 100% the same, so I harvested the armature and casing along with the inner gear from the replacement. I am happy to report that this worked and the shorting issue appears to be solved. I still need to hook up the fan motors, however that is a 'later' problem, after the car is plated,.


Jon