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Trans kickdown relay debugging

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Old Feb 26, 2011 | 06:00 PM
  #31  
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And..I didnt get 12v at the plug..but it was unplugged about 1/2 of an inch.


It may have gotten knocked out in the halfshaft/mount work back there, who knows.

But pulling it out to check for 12v has no resistance to removing it, but putting it back IN all the way, had resistance and a solid click.
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Old Feb 26, 2011 | 08:35 PM
  #32  
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I know the solenoid is hard to see and I had an extra so here are a couple of pic's

This 1st pic show the male part of the connector you are pluging the single wire into.



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Old Feb 26, 2011 | 09:20 PM
  #33  
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Tranny is full O fluid, and the solenoid is fully plugged in now..and if I give 12v to post 87a on the CE panel...I get clicks now.


Its the relay...darnit.
$75 from 928int.
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Old Feb 26, 2011 | 10:33 PM
  #34  
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ANyone see any issues if I removed the failed relay, and jumpered post 30 to 87a on the CD panel?

THis would trip the KD solenoid when the switch was hit..
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Old Feb 27, 2011 | 05:01 PM
  #35  
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Why do you think the relay has failed... I see no reason to assume this. Wally has already expained how the KD relay works - what you propose to do makes no sense (it just doesn't work that way - read it again). Button it up and try it as it is. If you really think the relay has failed (I think unlikely) - get another relay.

Alan
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Old Feb 27, 2011 | 05:12 PM
  #36  
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I think the relay has failed, because everything else in the system works fine.

Is there a test you think that I missed?
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Old Feb 27, 2011 | 05:41 PM
  #37  
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Relay is cheap. Stress medication is not.
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Old Feb 27, 2011 | 05:44 PM
  #38  
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No stress..was fun chasing it down.
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Old Feb 27, 2011 | 07:16 PM
  #39  
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Well I rather thought you said you had power at 87a - but did you just mean you manually provided power at 87a to get the solenoid to worek. KD Relay default is 30 connected to 87a - so you should be abel to test this with the relay on a bench...

If you just put a jumper in place of the relay you will get kick down initiation - but you won't get upshifts at the right point since the relay dropping out is what gives you this - and it won't ever drop out (this would be bad - you can over rev the transmission).

Just get the relay... but do check fuse 10 first....

Alan
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Old Feb 27, 2011 | 07:26 PM
  #40  
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can you not check the relay?

look on the relay and it will have a diagram with numbers...
the two lines that go to the coil are the wires from the switch. they will energize the coil and close the circuit.

run 12v to one side of the coil, and ground the other.
this should close the contacts.. then you would have continuity between those two post.
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Old Feb 27, 2011 | 07:52 PM
  #41  
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Originally Posted by yardpro
can you not check the relay?

look on the relay and it will have a diagram with numbers...
the two lines that go to the coil are the wires from the switch. they will energize the coil and close the circuit.

run 12v to one side of the coil, and ground the other.
this should close the contacts.. then you would have continuity between those two post.
No - this relay doesn't work that way. When activated these contacts break - not make. However can be tested as I noted - to not have 12v at solenoid w/ kick-down switch active & ignition on either the relay contacts don't connect, the fuse or wiring is bad or the switch is bad...

Alan
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Old Feb 27, 2011 | 07:59 PM
  #42  
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oh, so if it is a normally closed then the non coil posts should show continuity...then none when energized.
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Old Feb 27, 2011 | 10:33 PM
  #43  
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Originally Posted by Alan
Well I rather thought you said you had power at 87a - but did you just mean you manually provided power at 87a to get the solenoid to worek. KD Relay default is 30 connected to 87a - so you should be abel to test this with the relay on a bench...

If you just put a jumper in place of the relay you will get kick down initiation - but you won't get upshifts at the right point since the relay dropping out is what gives you this - and it won't ever drop out (this would be bad - you can over rev the transmission).

Just get the relay... but do check fuse 10 first....

Alan
Fuse 10 is good, as noted, I can follow 12v from that fuse, all the way to post 30 in the CE panel...just never gets thru the relay to 87a...but if I give 87a power at the panel, the solenoid clicks.


Should have the relay on Wednesday.
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Old Sep 15, 2013 | 09:34 PM
  #44  
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Grr...boomerang- so did the relay R&R remedy the problem?
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Old Feb 14, 2019 | 11:56 PM
  #45  
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Necroposting for a local owner...

He has no kickdown action, but the circuit is fully functional, we get good click action at the solenoid.

Can it be electrically good, but mechanically broken?
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