Electrical help

[walker111]

Only thing I can think of, is that the on off switch on the factory cruise control is a switch, not a press on press off, if you know what I mean.

 

[walker111]

Let's investigate each individual setting, one at a time. Move the settings back to NO because that's how all the signaling should work.

If you have everything wired, including the relay as per the above drawing, you should hear the relay click as it engages when you switch the cruise on.

You should also be able to measure the COM terminal and see 0 VDC.

When you tap the set switch, the COM terminal should briefly jump to 12 VDC and then fall back to zero.

The above to measurements are with reference to (wrt) ground.

How are those actions working?

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The relay only clicks when I hit set. Nothing when I turn it on/off

COM has 12v

 

[walker111]

Delete this post

 

[RamDiver]

The relay only clicks when I hit set. Nothing when I turn it on/off

COM has 12v

That's interesting.

This would suggest that the BR/RD is normally low and goes high when you press the set button, unlike the diesel supplement drawing in post #15.

The BR/RD is connected to the relay coil and if it was normally high (12VDC), when the CC was activated, the relay would be energized. This is according to the diesel supplement drawing.

In your posts, 1 & 9, all of the OEM switches are normally open (0VDC).
In your post 15, with the diesel supplement, BR/RD is connected to the OEM set/coast switch which is normally high (12VDC).

The circuit design is based on the diesel supplement drawing. If that drawing is wrong, so is the circuit design.


This should be a lesson for us both, don't trust any manual or word of mouth. Test the circuit first and you will know the true state.


Disconnect C211 and measure the voltage on the switch side of pin 4.
I'm guessing you will see 0VDC until you press the set button, then 12VDC.




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[walker111]

Br/rd definitely has power at the switch, hard to think I have a bad relay but I’ll try another relay.

 

[RamDiver]

Br/rd definitely has power at the switch, hard to think I have a bad relay but I’ll try another relay.

Wait!

Let's discuss this before you take any action.

If BR/RD is normally at 12VDC and it is connected to the relay terminal 85, the relay should be energized.

You say the relay isn't energized until you press the set button yet the BR/RD has 12VDC.
Those 2 conditions are contradictory if the wiring to the relay is the same as the drawing.

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[walker111]

Did you see my drawing? It’s exactly like that, which is like yours.

 

[RamDiver]

Did you see my drawing? It’s exactly like that, which is like yours.

OK, you say that BR/RD has 12V at the switch, then, you should have 12V at relay terminal 85 because the BR/RD is connected there.

Do you agree? Have you measured 12V at both the switch end and at relay terminal 85?

Are you using the same ground reference for the negative test lead on the multimeter?

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[Joseph Godvin]

My opinion is your way over thinking this........not gonna end well !!! Mechanic for over 40 years.....Not close to being a "parts changer" !!!!

 

[walker111]

My opinion is your way over thinking this........not gonna end well !!! Mechanic for over 40 years.....Not close to being a "parts changer" !!!!

Great advice. Wait…there wasn’t any.