Understanding of your vehicle's trouble codes

First off this information is intended for your knowledge only. This is not a substitute for any specialized training that may be needed for your specific problem. That being said this list presents a general assortment of domestic generic obd2 codes (vehicles 96/present). Certain makes have their own specialized codes which may differ from these. Here is the basic breakdown of the obd code: you'll have a letter first and four numbers, the letters are p/powertrain, b/body, c/chassis, and u/network (most trouble codes listed on this site are p codes). The first number will be either a 0 or 1. 0 is a generic listing, 1 means it is a manufactuers specific code (remember I mentioned there are other variations like p2**** etc. they are not mentioned here). The second number represents the type of problem you'll encounter 1 being fuel & air metering, 2 is for injector circuit problems, 3 is misfires or faulty ignition system components 4 is emissions related 5 controls vehicles speed and idle 6 is for computer and auxiliary outputs 7 & 8 refer to faults in your transmission. The last 2 numbers in the code represent the problem. I will not list all of them, but I'll list a broad enough spectrum to give you an educated point of reference to check. p0100 mass or volume air flow circuit malfunction p0101 mass or volume air flow performance problem, p0102 mass or volume air flow cicuit low input p0103 circuit high input p0104 circuit intermittent p0105-9 manifold air pressure circuit problem p0111-14 intake air control circuit p0115-19 engine coolant temp. circuit p0120-24 throttle positioning sensor circuit p0125-26 insufficient coolant temp. p0126-167 O2 sensor problems p0170-75 fuel trim (too rich or lean) p0176-79 fuel composition sensor circuit p0180-89 fuel temp. sensor circuit p0190-94 fuel rail pressure p0195-99 engine oil temp sensor. Now into fuel injection injector circuit section: p0200-212 injector circuit malfunction p0213-14 cold start injector p0215 engine shutoff solenoid (Now that we know these are all p0 series codes I'll save myself some typing) 216 injection timing control 217 engine overheating condition 218 transmission overheating 219 engine reached speed limit (limiter) 220-29 throttle/pedal position sensor 230-33 fuel pump 234 engine overboost (turbo) 235-42 turbo boost sensors 243-250 wastegate solenoids 251-260 injection pump fuel metering controls 261-96 cylinder injection circuit faults. Now the p03 series, ignition system and misfires 300 mulitple misfire 301-12 represent those cylinders misfiring (1 for cyl. 1 and 5 for cyl. 5 etc.) 320-23 engine speed input 325-34 knock sensors 335-39 crankshaft positioning sensor 340-44 camshaft positioning sensor 350-62 these represent ignition coils (same as 301-312 did with cylinders above) 370-79 timing reference signal 380-81 glow plug heater circuit (diesel) 382 bad egr (exhaust gas recirculation) 385-89 crankshaft position sensor b. Now the p04 series for emissions related problems 400-08 exhaust gas recirculation flow (low or high) or circuit malfunction 410-19 secondary air injection system 420-34 catalyst system 440-55 evaporative emission control systems 460-64 fuel level sensor 465-69 purge flow sensor 470-79 exhaust pressure sensor/controls 480-85 electric cooling fans. Now onto the p05 series for idle/speed control 500-03 vehicle speed sensor 505-07 idle control system 510 closed throttle positioning switch 520-23 engine oil pressure sensor 530-34 a/c refrigerant pressure sensor 550-54 power steering pressure sensor 560-64 system voltage problems 565-599 are cruise control related. Now the p06 series for your computer output 600 communication link problem 601 internal control module memory 602 bad module programming 603 module kam error (keep alive memory) 604 module ram error (random access memory) 605 module rom error (read only memory) 606 pcm fault(powertrain control module) 608-9 control module vss output malfunction (in electronic circuits vss is the positive supply and vdd in the negative/ground source s=source and d=drain on mos transistor devices) 650 mil lamp circuit (malfunction indicator lamp or simply your check engine light) 654 engine rpm (revoultions per minute) output 656 fuel level output. Now for sections p07&800s transmissions (This section will be brief, I hate working on transmissions and do not specialize in them. A simple piece of debris/dirt when reassembling a rebuilt transmission in the valve body is enough to cause it to wear out rather quickly. Without the proper training and test equipment this is the most difficult part of the vehicle to diagnose or fix). p0700-02 transmission control system 703 torque converter/brake 705-709 trans. range sensor 710-14 trans. fluid temp. sensor 715-718 input/turbine speed 720-23 output speed sensor 725-29 engine speed input 730 incorrect gear ratio 731-35 are incorrect gear ratios for those individual gears (same as p0301-12) 736 incorrect reverse gear 740-44 torque converte clutch 745-49 pressure control solenoid 750-74 shift solenoid malfunctions 780 shift malfunction 781 1st-2nd shift 782 2nd-3rd 783 3rd-4th 784 4th-5th 785-89 shift/timing solenoid 790 normal/performance switch circuit 801 reverse inhibit control 803 1st-4th upshift (skip shift) solenoid control. I hope these definitions have given you a better understanding of where your problem/s may be located. To determine the exact problem like a low circuit voltage input etc, etc. your specific code/s will be needed to give you that more detailed info. If you provide me with that info along with the specifics of your vehicle: year, make, model, engine size and a brief description of the problem you've had I'd be glad to help you in anyway I can. Thanks again for using fixya your source for the answers you need for everyday problems. Posted by Edwin37323