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2003 GMC sierra 1500HD with battery drain. Found

2003 GMC sierra 1500HD with battery drain. Found fuses HVAC/ECAS PCM B and TBC BATT to have amperage draw when engine is off (about 5 amps each). Disconnected help. Disconnected all fuses and relays no help. Appears healdight "high beam" idiot light is dimly lit at times....even with engine off. Seem to now have a low idle problem...not sure if its tied together or not. Battery was replaced a few weeks ago.

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Where is the power supply for the pcm fuse 2006 gmc sierra 1500

I, feel sorry for you, after reading your problem, but don't worry you visit the Reliable-Store they will help you for sure.
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Oct 05, 2016 | 2006 GMC Sierra 1500HD

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No defrost

Did you preform recalibration after replacement ? See if this works ,if not you'll need to take it to the dealer an have it done with factory scan tool .
Alternate Method (w/o Scan Tool)
  1. Clear all DTCs.
  2. Place the ignition switch to the OFF position.
  3. Install the HVAC actuator.
  4. Connect all previously disconnected components.
  5. Remove the HVAC/ECAS fuse for a minimum of 10 seconds.
  6. Install the HVAC/ECAS fuse.
  7. Start the vehicle.
  8. Wait 40 seconds for the HVAC control module to self-calibrate.
  9. Verify that no DTCs have set as current DTCs.

Sep 25, 2016 | 2010 Buick Enclave

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Where is the fuse for the heater located in a 2008 gmc sierra

Do you have The Automatic or Manual HVAC system ? Doesn't matter fuse's are the same ! Out in the under hood fuse / relay box are two fuse's for heater HVAC BATT fuse #39 10 amp an # 70 40 amp . HVAC BLWR . HVAC = heater ventilation an air conditioning ! So Tom what problem are you having ? Heater fan not working ? There is also a blower motor control module involved !

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1 Answer

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You can start by trying an actuator recalication.(w/o scan tool)

1. clear all DTCs by disconnecting the battery.

2. remove the HVAC/ECAS fuse for a minmum of 10 seconds.

3. install the HVAC/ECAS fuse.

4. start the vehicle.

5. Wait 40 seconds for the HVAC control module to self-calibrate.
If this doesnot work, probably the right actuator is defective. You
will have to replace it. In the center of the HVAC module, there are two actuators, one is on the top part of the module and the other one is Under. The right actuator is the top one.

Jul 09, 2014 | 2009 Chevrolet Silverado 1500

1 Answer

2003 GMC Sierra 1500. I was backing into my driveway and the truck just died. No electrical power at all. None! Could the problem be associated with the anti-theft system?

cud--but test alternator and make sure batt is holden 12.6v at all times--also inspect wiring and chec fuses and maxi fuses under hood--with older cars components wear and gain resistence too causing blacout until vehicle cools down

Oct 06, 2013 | 2003 GMC Sierra 1500

2 Answers

TBC Batt fuse is draining battery after car set 24 hrs what is this fuse for

This fuse is for the body control module, so your draw is probably something controled by the bcm. Get a manusl, get a list, and eliminate them one by one until your draw is gone! Good luck, let me know if you need any more help!

Feb 11, 2012 | 2003 Chevrolet Silverado 1500

1 Answer

2001 GMC Sierra headlights won't come on. Located 3 each 10Amp fuses that were blown and replaced them, however, headlights didn't come on.

what fuses were blown and replaced? Theres a TBC fuse under the hood, along with a Headlamp Relay. Theres a R HDLP and LT HDLP fuses, make sure they are getting power, and are good. If the LT HDLP and RT HDLP fuses are good AND getting power, then the TBC fuse and the relay is good. then I would suspect the Hi-Lo dimmer switch bad. The LOW beam ground wire is YELLOW, the high beam ground is PURPLE. see if high beams work, if they do, then I suspect the dimmer switch is bad.

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1 Answer

2001 gmc sierra, light under the hood is out. where is the fuse for it

In the fuse box under the hood Its the one marked TBC second across from CTBY LP Bottom row its the last one. That where it is on our truck but its a 2000 GMC you could try it.

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1 Answer

Trailer brake controller problem

I found the problem. Talking with a technician from the controller company, we determined that it was a fuse problem. I found that the fuse to the CHMSL was blown.

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1 Answer

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Need to have your HVAC system scanned to determine what has failed in that system. Possible blend door for drivers side or maybe the system just needs recalibrated.

Oct 01, 2008 | 2006 GMC Sierra 1500HD

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