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Old 04-23-2017, 08:02 PM
Shern's Avatar
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Installing new ignition/ testing circuits

Migrating this from the "bloody blower motor"/fuse 8 thread.

I've pulled the ignition tumbler/lock/switch mechanism.
Before I examine that, I'd like to make sure 15x is getting juice.
From what I understand, the key is what activates this circuit, meaning that if I stuck a multimeter onto the 15x plug on the connector and reconnected the battery, it would probably read cold. Am I missing something? (everything?)

How do I test circuit 15x, if it's only turned on through operation of the ignition switch?

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Old 04-23-2017, 10:19 PM
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Set multimeter to the appropriate DC scale. Red lead on the 15x terminal, black lead touching a good ground point. Turn key to "Run". You should have 12V reading from 15x to the ground point.
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Old 04-23-2017, 10:31 PM
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This might sound a little ridiculous, but where can the terminal be accessed if not within the plug itself? Where is the terminal? I assumed it was at the switch/within the switch.

Edit for clarity -with ignition switch unplugged, is there still a cable form the ignition assembly registering to the electrical system that the key has been turned?

Last edited by Shern; 04-23-2017 at 10:53 PM.
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Old 04-23-2017, 10:36 PM
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If you're testing a circuit in-place, the plug has to remain connected to the switch that you're testing. Obviously this means you can't simply probe the plug that connects to the switch because it won't be powered. You'll have to examine the plug and find out if you can probe through the back of the plug or otherwise probe the pin you're trying to test. You may have to remove the switch mechanism from the lock mechanism to get enough clearance to do what you want.

An alternative approach is to find where power comes into your switch and where the 15x terminal is. Set your multimeter to the Rx1 ohms scale and read across those pins. Turn the switch to "RUN" and you should read a dead-short (0 ohms). If you're open or have resistance the contacts are no good.
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Old 04-23-2017, 11:23 PM
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figured it out... there's a yellow cable connecting the entire assembly to mains power. basically, you can unplug the terminal plug and test that while articulating the key and everything responds as usual.

Much appreciated.
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Old 04-24-2017, 04:58 PM
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That funny. I am looking at the wiring diagram and it has terminal 15X at the ignition switch (in run) and the wire is Red with a Yellow stripe and it goes fron there to Fuse #8 which is listed as 16 amps and from the fuse box to the Heater and Air Conditioning.

That means if you remove Fuse #8 and put the ignition switch in run one side of the where the fuse connects should get Voltage. The other side of the fuse conector represents the wires going to the AC and heater controls.

Replace the Fuse.
The that goes from the fues box to the AC/Heater is color is BK/CN/PK I think what llooks like CN is actually Gn for green but I am not sure. Anyway you might be able to see enough of the wire at the Fuse Box to determine the color.

If you acces the connector in the AC/Heater control you should see that same color of wire at tne Connector. In Run you should get Voltage at the Connector for that coloed wire.

Terminals on the Blower AC/Heater switch, 6 Gr/Yl/BK Goes to the Blower Motor and one the Resistor but the blower motor wire turns red before it gets to the resistor and the resistor wire turns to green, 4 goes to the resistor starts off green yellow but turns to gray, and 2 goes to the resistor the wire starts off ad Gn/RO and I don't know what RO is however it turns into yellow.

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