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1968 Continental Sedan Electrical Issues & Follow Up

Hello Bill -

The window operation and A/C operation will only work with window bypass switch in the bypass position. I can find no relationship between these two circuits other than the circuit breaker panel. I recently inherited this vehicle and the A/C compressor and clutch needed replaced. System also converted to R134a. But I do not know if this issue was prior to the replacement or not. Please advise.

Thanks,

Greg

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Greetings Greg -

The a/c and p/w circuits should also be energized with the ignition switch in the " accessory" and the "engine run" positions well as with the by-pass switch engaged. The following advice can be helpful to you only if the involved wiring circuits have not been previously modified, damaged or tampered with.

Power from the ignition switch in the accessory or run position leaves the switch on a Black wire with a green stripe. It then is sent to the fuse box and through a 14 amp fuse and then to a relay known as the "Power Window Safety Relay". The relay is activated by this wire and connects the remaining two wires together to power up the windows and the HVAC. One of these wires will be live with power from the battery at all times. This relay is located behind the rt. front wheel. It is accessible by removing the rt. front wheel and the splash shield behind the wheel. The above circuit and relay should be tested as a first step. I would start at the correct 14 amp fuse in the fuse box because you can test the ignition output to the fuse and the fuse itself at the same time. If everything checks out to the relay and you are not sure how to test this relay we can offer to test it for you. We can repair these relays ( if faulty ) or supply a replacement. Good luck with the repair.

Sincerely,

Bill

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Bill:

Seems to be spot on. Actually the blower will run with the ignition off. I have the wire as number 297 & 297A thru fuse to 911 to 194A to relay. So to help me understand, is this relay causing a break in the circuit and the switch in bypass completes the circuit?

I do not believe any of this has been tampered with. I need to check that the amperage is correct on the fuse. The A/C folks may have put in a larger fuse which may have damaged the relay. Would a larger fuse cause this?

Thank you,

Greg

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Bill:

The fuse is correct size and nothing appears to be tampered with. I will need to rebuild or replace the relay.

I have another question. My interpretation (based on page 16-30) of the automatic climate control A/C function is that the compressor clutch is continuously engaged unless the ambient temperature is below 35 degrees F. Is this correct?

Thank you,

Greg

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Hi Greg -

In your first email to us you asked for my advice. I spent over an hour researching and laying out a way for you to follow the power path to the Relay from the ignition switch. Diagnosing in a logical sequence is the only way to identify the problem. Your two replies tell me that all you have done is to look at the amperage of the fuse in question. We are not even advised if there is any power to this fuse from the ignition switch. You also have more questions that are unrelated to your opening statements.

What you need to do is to follow the power path as I described to the relay to determine if the relay is present and if the relay is actually being energized. If it is being energized and is audibly working it will ( if it is in working order ) connect the other two wires and energize the circuit. One of these other two wires must of course have battery power at all times. When you have performed some meaningful diagnoses please report back to us for some further suggestions if necessary.

Sincerely,

Bill

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Greg -

Do not use the Bypass switch at all while testing this circuit. Is power available at the relay from the 14 amp fuse with the ignition in the run position? If the answer is "no", someone needs to diagnose that circuit further. If the answer is "yes" and the relay does not respond then the relay could be faulty or the wires to the relay are somehow incorrectly attached or the relay ground circuit is poor. If you suspect a problem relay, send it to us for proper testing as mentioned in my first reply. Call our office and George will arrange this for you. Remember that one wire at the relay must be live at all times ( key in any position) with battery power. A second wire will be energized with the key on in the run or accessory position.

Sincerely,

Bill