How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Pete Your Own Question
Pete
Pete, GMC Mechanic
Category: GMC
Satisfied Customers: 28763
Experience:  GM training and dealer tech for 14+ years. Diagnostics
14928985
Type Your GMC Question Here...
Pete is online now
A new question is answered every 9 seconds

I don't have a pontiac, i have a 2005 gmc 2500hd 6.6

Customer Question

i don't have a pontiac, i have a 2005 gmc 2500hd 6.6 druramax. throwing all sorts of codes
C0055
P0721
P0876
P0401
P0404
P0500
P0670
P0700
C0035
U1000
C0040
B2600
Submitted: 10 months ago.
Category: GMC
Expert:  Pete replied 10 months ago.

Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.

Have you cleared out these codes to see if all of these codes come back again or which codes come back again?

Let me know so we can continue,thanks Pete

Customer: replied 10 months ago.
have cleared them in order to program the speedometer.
Customer: replied 10 months ago.
The speedometer now matches actual speed so now maybe the speed sensor codes may go away
Customer: replied 10 months ago.
But the service brake system light is still an issue
Expert:  Pete replied 10 months ago.

And to be sure all of these codes are now coming back again?

Customer: replied 10 months ago.
Checking now
Expert:  Pete replied 10 months ago.

O.k.,let me know when your ready.

Thanks Pete

Customer: replied 10 months ago.
Now I'm getting just 2 codesC0055
P0670
Expert:  Pete replied 10 months ago.

O.k.,looking into these codes now,Will post back here shortly.

Expert:  Pete replied 10 months ago.

P0670 is glow plug control module circuit fault.This can be one or more of the glow plugs at fault or the glow plug controller as well as wiring issues to the glow plug controller itself.Below is the diagnostic info for this code.

https://www.dropbox.com/s/cgl32vvucye69io/g-11-22.gif?dl=0

https://www.dropbox.com/s/jap4ifrjh5wooma/gl-11-22.gif?dl=0

C0055 indicates rear wheel speed sensor both wheels at fault.This leads to a faulty EBCM or PCM in most cases.Below is the diagnostics that need followed for this code here as well.

https://www.dropbox.com/s/lomekpmvf3r3o0v/c-11-22.gif?dl=0

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service,your 5 star rating is appreciated.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.

Thanks Pete