• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

What is this? Related to EAP?

robertmee

Full Member
Joined
Jan 25, 2018
Messages
133
Location
Raleigh, NC
Working on diagnosing my Adjustable Pedals.  I can hear the relay click in both directions (which btw, where is the relay?  It sounds like it's behind the dash somewhere, not in the fuse panel).

So, I crawled under the dash and found this hanging.  That doesn't look right and looks like it could be a reversing motor (two coils and a shaft).  It has a connector on it.  Is this related to the EAP or something else I have wrong?

wPVIZjP9kF6kkl7_lhAeF_KrZUNbOSTW5T2DZaTqhHlAy-DOtvFkPBufnXE5c5kguPYt26MAiQUmfcoOO6OZBC_sVjhzmqtxa56itNlSU_jDkdcrxkFAXjHh6ZLPvp2EMYnB62KshQ=w475-h844-no


If you can't see the above image, it's the last picture in this gallery:  https://photos.google.com/share/AF1QipNnUXoWbs82wwNdtZx_DE53mk-aSTLSUQkGuf-BuWXl8MYUqLOWlvg9ZNsipgkbRg?key=VG5ob0J5bjlEQzVzenZBVnVBOUpSMWJwMWdaR013
 
Well it kinda looks like the motor that would move your pedals near and far!

Didit
 
robertmee said:
Working on diagnosing my Adjustable Pedals.  I can hear the relay click in both directions (which btw, where is the relay?  It sounds like it's behind the dash somewhere, not in the fuse panel).

So, I crawled under the dash and found this hanging.  That doesn't look right and looks like it could be a reversing motor (two coils and a shaft).  It has a connector on it.  Is this related to the EAP or something else I have wrong?

That looks like the motor for the brake pedal.
It should have a silver cover over it and a white plastic plug/shaft that slides over that shaft in the center so you can manually turn it w/ a #3 or #4 phillips and also connects the linkage to the brake pedal shaft. Without the cover/linkage, your brake pedal won't move.
Does the gas pedal move when you try to adjust?
Does the shaft visible here turn when pressing the switch?
If you look to the right of this area (at the upper left of the gas pedal shaft)you should see a similar plastic plug in a black cover that lets you manually adjust the gas pedal
If neither the gas pedal or this shaft move, check the purple wire and the black/orange for continuity.  The purple wire goes between the relay and the plug pictured and is the control wire for forward and the black/orange is for reverse if I remember correctly.
The motor in your picture is under this cover/linkage assembly
 

Attachments

  • pedal motor linkage.jpg
    pedal motor linkage.jpg
    57.8 KB · Views: 18
Mike is right about that connector, and the relay is under that panel that is in the picture.
 
Thanks so much for the help!!

Okay, so the cover with the plastic hex nut has the relay behind it?  I took it off and exercised the switches on the door panel, and it didn't sound like the relay clicks came from there, but I'll check again.

No, the shaft doesn't turn.  That was my first thought too.  And no, the gas pedal doesn't move either.

I'll grab my meter and check those wires....member itsstopher was kind enough to email me the schematic so I'm clear on the wiring.

 
Definitely the motor is detached.

So, I have a clearer picture now of this assembly.  The grey piece in the picture with the red arrow, is the gear assembly for the brake pedal.  The motor sits on top of that (what's pictured in my post).  On top of that motor integrated is a gear cable that goes over to the accelerator pedal and drives its gear.  So this one tiny motor drives both pedals.

So, I have two problems.  The motor shaft isn't turning so either no power or no ground.  The two relays send either ground or VDC down the purple and orange/black wire depending on direction.  In the pedal forward, the orange/black gets VDC while the purple is ground.  In the pedal reverse, the orange/black gets ground while the purple gets VDC to reverse direction.  In the off state, both orange/black and purple are tied to ground.

I know I'm not missing ground, because the relay coils use the same ground and they are switching.  So I must be either missing power or the motor itself is FUBAR.  It's doubtful I have broken wires on both Purple and orange/black to cause neither direction to work.  So, I'm guessing that the main power from the 15A EAP fuse in the engine compartment is not getting to the relay contacts.  This is an Orange wire labeled 3940.  Or the motor is just plain toast.  Next test will be to put my DVM on the connector and test for voltage.

The 2nd problem I have is the motor assemblage.  Why was it off in the first place.  I'm guessing maybe the previous owner tried to fix and gave up?  In any case, I'm missing the two screws that hold it down.
 
If there is another cover that looks like that one near the kick panel, that is where the relay is, my seat heater element is bad and had to pull the relay and that controls all of that.  R 
 
ronthehandymanga said:
If there is another cover that looks like that one near the kick panel, that is where the relay is, my seat heater element is bad and had to pull the relay and that controls all of that.  R

Yeah, I'm going to have to find that relay.  I took my DVM and I had no power at either the orange/black or purple, when exercising the relays.  I also had no continuity to either in the off state to ground, which is odd.  It's almost like the harness at the relay has pulled free.

I swear though, when using the buttons, the relay clicks sound much higher in the dash.  Almost behind the hvac vent on the driver side.  Might just be the way the sound is traveling.  I did take the lower knee blocker off and that didn't help expose much.
 
robertmee said:
I swear though, when using the buttons, the relay clicks sound much higher in the dash.  Almost behind the hvac vent on the driver side.  Might just be the way the sound is traveling.  I did take the lower knee blocker off and that didn't help expose much.

Echos can be deceiving. Try resting your fingers lightly on the relays. You should be able to feel which one is clicking.
 
buickwagon said:
Echos can be deceiving. Try resting your fingers lightly on the relays. You should be able to feel which one is clicking.

A member sent me this...shows the relay (#4), Above the motor which is about where I'm hearing the clicking.  Not behind that cover?

normal_eap.png
 
Mine is not in that location. Glad you know were it is.
 
Back
Top