Gmc codes without scan - Sierra GMC Cars & Trucks

You should take it to a garage that has a GMC scan tool and scan it for the error code.

What kind of scan tool did you use to pull this code ! My Factory GMC service info doesn't list this code ! My info shows P0030 - P0036 ! You have to watch with aftermarket code readers ,they tell you wrong codes ! Need to validate with factory scan tool !

This could be a few things that could cause this problem...Do you always hear the blower motor run with or without heat..?..knowing this would help me answer your question...It could be the heat blend door inside Your HVAC system behind dash ..These doors can stick or break..The best thing you can do other than trying to troubleshoot everything ,guessing and getting a headache is take it to a dealer and let them scan the system...They can find the problem with or without a trouble code...It may cost $ 100,00 dollars to have it scanned however it will save you money in the long run...

You can go to Autozone and they will do a scan for you (usually for free) to get the codes. Unfortunately there isn't a way to read the codes without hooking it up to a machine that can read the codes.

You will need to have the computer scanned to get the trouble codes.
You can try troubleshooting it the hard way without the codes, but its complicated.

SEEMS THAT YOUR ACTUAL ABS MOTOR MAY NEED REPLACED, HAVE YOU CHECKED THE FLUID LEVEL?? I HAVE ALSO FOUND IN THE PAST, YOU WILL NEED AN ACTUAL SCAN TOOL THAT WILL WORK JUST FOR THE ABS BRAKE SYSTEMS, AS A REGULAR SCAN TOOL DOES NOT WORK ON ABS BRAKES, IT HAS TO HAVE THE ABS PROGRAM IN THE ACTUAL SCAN TOOL, THEN IT WILL GIVE YOU THE PROPER CODE. YOU MAY TRY AUTOZONE, AS THEY CAN USUALLY SCAN ONE WITH ABS, WITHOUT CHARGING YOU ANY FEES, BUT GET YOU THE CORRECT ERROR CODE JUST FOR THE ABS SYSTEM, THEN YOU WILL KNOW EXACTLY WHAT THE PROBLEM IS......

Is your "Check Engine" or "Service Engine" light on? Scan your onboard computer system for possible fault codes even if your engine light is not on. There are some fault codes that can set without turning the light on.

If there are no fault codes, there is not much you can do other than performing normal maintenance like replacing the air filter and fuel filter.

The first step with a problem like this is to have the electronic engine control system tested for fault codes, you may have a defective idle speed control system, if this is the case you will also need a "Engine Running" fault code scan as well as a passive memory scan. The 2 tests are referred to as the the Key on engine running test (KOER) and the Key on engine off test (KOEO)

most of the newer vehicles its almost impossible to do without a scan tool, but some vehicles can be reset by simply removing the battery cables for a few minutes and put them back on... keep in mind though, if you do that, make sure you have the original key and keyless entry remote if it has one, if it has a theft lock stereo, get the code out of it first, and realize that some vehicles once reset has got to sit and idle, and teach itself how to idle again, then you drive it, how you would normally drive it for a few miles, and let it teach itself the shift points again.. hope this helps.

A number of Auto parts stores offer "FREE" diagnostic scans in the hopes that you will buy their parts although most have a "no obligation" policy. Autozone .... Advance auto parts are a couple that offer free OBD II scans