Reading diagnostic fault codes is just the starting point in the diagnosis. They never say to replace parts or that they're defective. They only indicate the circuit or system that needs further diagnosis, or the unacceptable operating condition. When a part, usually a sensor, is referenced in a code, that part is actually the cause of the code about half of the time. First we have to check wires, connector terminals, and mechanical problems related to the circuit, then perform voltage and continuity tests, and finally replace a part if everything is ruled out.
There are entire books that detail the numerous steps to diagnose each fault code. If you're going to do a lot of your own repairs, look for those books on places like eBay, or you can go to the top of this page and point to "Repair and Service", then click on "Manuals". That will take you to a place where you can buy a subscription for your vehicle from an online service manual company. That will also get you to the troubleshooting steps for these codes.
The cost of a subscription for one vehicle is very small compared to what repair shops pay every year, and you'll save more than that on one repair that you can do yourself. You'll also find circuit descriptions that will tell you how various things are supposed to work. Those can help you determine right away if it's something you can tackle, or when it's time to see your mechanic.
Monday, June 22nd, 2015 AT 10:14 PM