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switchover valve question

I am testing the pods and switchover valves for my 1984 300SD.

I'm using a mityvac and hooking it up to the switchover valve pointing away from the dash part "A" shown in the link below.

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It's supposed to hold a vacuum with the power off and then open up when current is applied.

One of the switchover valves failed this test and so I tried switching wires with another valve and this valve passed the test. Bad wire?

My valves are numbered 1-6. What do these go to? The diagrams I've seen only have five switchover valves. I guess for a W123.

Thanks, Jeff

Reply to
Rooster
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Possibly, but I doubt it. Wire under the dash is usually well protected and doesn't fail. Wire usually doesn;t fail unless it;s exposed to a harsh environment like heat, UV rays, etc. that cause the insulation to fail and a short. Then it should blow a fuse.

I'd suspect a loose connection, bad switch, or that whatever generates the current to commmand the change over isn;t generating it. In general, with an air circulation flap, that command can depend on one or more conditions from another switch, sensor for vacuum, temp, etc that is totally unrelated to the wire connected to the valve. You really need to trace a diagram that shows the circuit and what drives it.

Reply to
trader4

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