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Ask GM Tech (Cam) Your Own Question
GM Tech (Cam)
GM Tech (Cam), Chevy Technician
Category: Chevy
Satisfied Customers: 29569
Experience:  GM Grand Master Technician 2007. 14 years experience.
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Chevrolet 2500hd: 2002 chevy 2500hd... i replaced heater core

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2002 chevy 2500hd... i replaced heater core and put all back together and i have no brake lights or cruise control..cant figure out what i missed

GM Tech (Cam) :

Hello, I'm Cam. At anytime during our discussion you need more information or clarification, please reply.

GM Tech (Cam) :

Did you get the brake switch plugged back in on the switch and the junction block at the drivers left foot?

Customer: replied 5 years ago.
i know the brake switch is plugged in but im not sure what ur talking about junction block
Ok, do you have a test light that we can test with?
Customer: replied 5 years ago.
Ok, does the orange wire at the brake switch get power?
Customer: replied 5 years ago.
no power on orange wire
Tell me, does the stop lamp fuse get power?
Customer: replied 5 years ago.

yes it does


Ok, can you check the wires that run from the back to the fuse block in the dash then?

And the junction block to the left drivers foot, did you miss a connection there?

Can you pull the main connectors off and check for bent pins and such? This orange wire needs to get power all the time and that is why it is not working as it controls the brakes and the cruise. Check this out and see what happens.
Customer: replied 5 years ago.
i found i 4 wire plug that is not connected.. i cannot find where it goes branches out of a loom that continues up to roof liner and has a lt green/blk dk green/wht yellow/blk brown/wht wires
Where exactly did you find the wire/connector at?

Pictures would be helpful if you can.
Customer: replied 5 years ago.
on drivers side top of dash branching off wire loom that continues up the window pilar
That should not be related to the power on that orange wire.
Can you follow the wiring from the brake switch to the fuse block?
Customer: replied 5 years ago.
i have power to orange wire and still no brakes
When you press the brakes, does the white wire beside the orange get power?
Customer: replied 5 years ago.



Does the top cab brake light work?.
Customer: replied 5 years ago.
With your test light, does the VEH STOP fuse in the underhood fuse block get power with your foot on the brake?

Customer: replied 5 years ago.
no it does not ,no
That connector you found I believe is the key. With the diagnosis so far, we have narrowed it down to that connector. See the picture below.

the connector number is XXXXX
Customer: replied 5 years ago.
does that have the same color wires as i told u cus i cannot find the connection
Indeed it does. SO the end must be around there somewhere.

Customer: replied 5 years ago.
fyi we were talking about different plugs but i found all of them burried under defroster thank u very much
YOu got it working then, that’s great.

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