Hi Everyone, I had a bad Mass Air Flow Sensor that I replaced. Drives amazing now with this quick fix. My problem now is that my check-engine light is still on. I went back to Autozone, and of course, they said they can't reset it for me even thought the problem is fixed. I called the dealership, and they said they'll do it for a bazillion dollars. Not happening.

I've left the battery disconnected overnight, and this didn't do it, as somebody suggested here. Anyone else know now to do a hard reset to remove that annoying light? I know I must have a deeper problem in the ECU with a sensor, since my light is still on, but I'm just not willing to spend a grand on a $6k car that runs perfectly. I'll wait until that becomes a necessity.

Any help? What can I do to reset this thing myself?

Jeff
Phoenix, AZ
2002 X-Type 2.5

 

Battery disconnect should do it so you likely have a fault still. Just read the codes.

There's a thread in General Tech about which OBD tools are good. An elm327 will likely be fine for upwards of $10. Should read & clear codes.

 

Jeff, go back to the auto parts place and have them read the code again. If it is the same code, then you haven't fixed the root of the problem. If you have something else, then it will take some more work. Let us know what the code is and then we can possibly take it from there.

As for clearing the code, if you disconnected the battery, then the light should have gone off provided that all problems are resolved. By the fact that the light came back on, that is telling me that there is atleast 1 more thing that needs some TLC. It may be that with the MAF sensor now working, it is sensing a vacuum leak (P0171 or P0174).

LIke was previously mentioned, you can get an ELM 327 module and if you have an Android based smart phone, you can use that to read the codes yourself and also look at the engine parameters to see what is going on with your vehicle. Unfortunately, there is no app that I am aware of for Apple products. The other option is to get one of the WiFi units and if you have a laptop with WiFi capability, you can download programs and go at it that way. But, what a program would run, not sure. The ELM unit will run you about $15. I have the ELM 327 unit and the free app (called Torque) and I use that over my corded code reader made by Actron. The other nice thing is the ELM unit will work on other brands too should you have the need to work on something else. The only "limitation" that I have found is that the ELM unit only seems to work on the early 2004 and older Jaguars. Not sure how it may work with other manufacturers and what years it may be limited to.

 

Fixing the fault will not clear the DTC. It is in a NON-VOLATILE memory section of the ECM.

Removing power from the module will not erase the DTC (hence the term, non-volatile)

The DTC might clear itself after a certain number of cycles in which the fault does not reoccur.

I suggest you spend $30 or $40 on a cheap hand-held code reader to clear the DTCs.

If after clearing them, they are flagged again, then you still have a problem.

bob gauff

 

Thanks, everyone. I have the feeling I may have additional problems. Autozone diagnosed the issue with the air flow sensor, and I just bought it on the spot. I'm betting there is more to it. Runs so much better, but there may be more.

Bob, I'm going to grab one of those code readers. I'd been thinking about doing that for a while. At least then I'll know if I still have the issue after clearing them. Thanks again for your help.

Jeff