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Mechie3
10-16-2013, 10:18 AM
What is a "Reverse Circuit"?

It shows up multiple times in the wiring diagrams for the gauge cluster (aka: combination meter). At first I thought it was a reference to the actual "car is in reverse" circuit (aka, wiring path) but that didn't make sense as the FSM doesn't ever reference a "car in reverse circuit". Some google searches come up with info that leads me to believe it's a style of circuit that somehow reverses...something?

It shows the airbag system feeding into the gauge cluster and into an internal "reverse circuit". ABS warning light does the same as does the parking brake. I think I can remove these leads as the end not attached to the gauge cluster attach to items that are fully removed anyways. I just want confirmation.

I'm only an ME. I could use some EE help. :D

PhyrraM
10-16-2013, 10:36 AM
Can you post the diagram?

Many times OEM will use diodes to keep certain sections of the harness from being 'backfed' by a common component.

Mechie3
10-16-2013, 11:07 AM
Pink = items to delete
Blue = potential items to delete
purple = oops, this should be blue not pink
Red squiggly = not applicable (Manual AC vs Auto AC

I think I can delete the inputs B18 because it connects to the airbag module which will be gone.
C7 hooks to the fuse box (power) while C6 connects to ground. If these are feeding another circuit I don't want to remove them.

http://i.imgur.com/P6MOm02.jpg

Bob_n_Cincy
10-16-2013, 11:22 AM
What is a "Reverse Circuit"?

It shows up multiple times in the wiring diagrams for the gauge cluster (aka: combination meter). At first I thought it was a reference to the actual "car is in reverse" circuit (aka, wiring path) but that didn't make sense as the FSM doesn't ever reference a "car in reverse circuit". Some google searches come up with info that leads me to believe it's a style of circuit that somehow reverses...something?

It shows the airbag system feeding into the gauge cluster and into an internal "reverse circuit". ABS warning light does the same as does the parking brake. I think I can remove these leads as the end not attached to the gauge cluster attach to items that are fully removed anyways. I just want confirmation.

I'm only an ME. I could use some EE help. :D

Craig
the reverse circuit turns the light off when the signal is 12 volts.
it turns the light on at zero volts on the sensor wire.

The reason it does this is: If you unplug ABS or airbag. The light turns on.

To keep the light off you should jumper the +12 on pin c7 to pin B18 with the sensor wire deleted.

You could also disconnect the ground to pin to pin C6 to keep the light off.
Bob

Mechie3
10-16-2013, 11:50 AM
Awesome. I'll add that to my notes. It also occurs in the ABS system with C7, B3, and A1. I'll just have to toggle 0V and 12V to double check the light is turning off.

Thanks!