Select a Vehicle

Find parts for your specific vehicle

Choose your Vehicle

Having trouble finding a specific product?

1973 Mark IV Power Window & Horn Questions

Hello Bill –
I recently bought a ’73 Mark IV. None of the power windows work, and as far as I can tell I am not getting any power to the fuse. Is the relay before or after the fuse? Can a bad relay cause this? Also my horn does not work. I’ve taken the steering wheel off, and it seems like I am not getting any power to the steering wheel through the spring loaded contacts between the column and steering wheel. Do you have any tips?
Regards,
Jon
—————————————————————————————————————-
Greetings Jon –
The power window safety relay is before the p/w circuit breaker. That breaker is located at position f10 in the fuse panel according to my wiring diagram. A faulty power window safety relay can of course cause all of the power windows not to work.
The horn circuit is supplied power via breaker f12in the fuse panel using a yellow wire with a blue dot tracer according to the wiring diagram. Vehicles with the Speed Control option also employ a horn relay in the circuit.
Your question ” Do you have any tips” has one important answer from Lincoln Land. Performing any diagnosis on these circuits usually requires the use of the correct factory wiring diagrams and some electrical knowledge in order to understand the circuitry and locate most of the problems in a logical sequence. The best tool in your tool box could be the correct Wiring Diagram for your car. If you have recently purchased the Mark IV in this condition also be on the lookout for possible wiring misconnects and incorrect improvising from a previous owner. We wish you a speedy repair.
Sincerely,
Bill

Have a Question? Submit your question to Bill!

Submit Your Question

Your Selected Vehicle