Could Someone Please Explain
I'm sure some of you have probably seen some of my other posts about this, so please bear with me. I hate to ask what is probably a very elementary question, but I'm trying to get my head around exactly how the DPF and EGR sensors work. Some are pressure sensors and some are temperature sensors, that much I got. What I'm wondering about, is do these sensors have electrical connections to them? In other words, when the proper conditions exist to trigger a sensor, how does it communicate back to the computer to set the appropriate code, or start a regen, or whatever? I would think it would have to be physically wired somehow to accomplish this. For example, if I get a P2454 (DPF Pressure Sensor "A" Circuit Low), wouldn't that mean something in the electrical path is failing, and not necessarily the sensor itself? I would think so, especially since the sensor itself has been changed recently. I've got a gremlin that keeps throwing this code and setting the "check engine" light (although it's not on as of this writing). That's how I know the sensor is new. It threw the code and turned the light on so I took it in to the dealer. However, it's done it a couple of times since then which tells me it's obviously something else. Since I haven't had time to take it back to the dealer, I've just reset the codes so that I don't have to look at the light. I know that's not the best way and that the problem is still there and that I need to take it back in, but I mainly just want to know how the sensors communicate with the "mother ship", so to speak.
Last edited by cp2146; 11-22-2011 at 10:38 AM.