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300D Transmission Issues

Pursuant to a number of earlier posts, I have managed to free the kick- down button switch on the firewall of my 300D and believe that it can now be removed without breakage. I have not yet done so. However, would someone please explain in detail how this is supposed to remedy the problem of the transmission not shifting into top gear? I was not clear on that from the previous posts.

If indeed unplugging the switch restores the transmissions ability to shift into 4th gear, what then? Can the switch then be restored and the transmission will continue to function normally, or is this merely a diagnostic step leading to another procedure?

Sorry to seem dense on this, but I am just "not getting" how this whole lash-up works.

Thanks!

Reply to
randallbrink
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Kickdown switch forces the transmission to downshift and stay there until the switch release. As simple as I can explain it.

If disconnected and the tranny works normally, it means you need a new switch!

You are a bit 'dense'!

Reply to
Tiger

The kick-down switch energizes a solenoid in the transmission body (at the rear, most likely on the right side). This forces the transmission not go into 4th.

When the gas (or your diesel :-) pedal is pressed to the bottom, the switch is pushed in. Transmission down shifts to 3rd. The engine revs high and the car now accelerates fast.

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Reply to
Wan-ning Tan

Yes, I am a bit dense on this one! At any rate thanks very much for clearing this up, and I will go ahead and conduct the test today and replace the switch if, hopefully, this is the problem.

Reply to
randallbrink

Thanks. Makes sense now, and I will go ahead and do this and check it.

Reply to
randallbrink

^Ha ha. No offense, Randall, but that was funny, Tiger.

Reply to
runbiodiesel

That was the culprit. I was still not able to remove the switch, but was able to disconnect the wire, and then road test. Transmission shifted to all four gears.

Reply to
randallbrink

"Fast" is a relative term; we *are* talking about a 300D, here.

Reply to
Alec Lourmier

Great!

How is your slipping after disconnecting? Did it help?

Reply to
Tiger

It didn't seem to change much, but I have not yet adjusted that vacuum modulator on the transmission. I think that will take the slipping out.

Reply to
randallbrink

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