De-marko
Dedicated LVC Member
Wow! Good sleuthing. I like hearing that people get there strange issues fixed. 
New and looking for some help.
- Thread starter Rifleman@LaymansPC.com
- Start date
Rifleman@LaymansPC.com
Well-Known LVC Member
Not sure how it all works, just relaying what was explained to me about the sensor. They're now using a MAF Module that has the MAF sensor, the MAP sensor, and the Intake Air Temp sensor.
When I had first encountered the issue, I was looking high and low all over the upper and lower intake for any sorta sensors I couldn't identify visually or by part number on the net. Couldn't find it. At that time I had spoke to a VERY knowledgable mechanic, that knows the processes, but doesn't know the LS too well. He explained that the MAP sensor is simply a Barometric sensor that senses the altitude and adjusts the mix accordingly. He said newer sensors are primarily electronic and don't need to be mounted in or attached to the manifold itself to do their job anymore. Older passive units did.
Either way, it's supposed to be a very hearty unit.
Maybe Maxx could shed some extra light on the internals of the sensor.
Rifleman@LaymansPC.com
Well-Known LVC Member
The warning appears all the time off and on, doesn't matter what it's doing. When it first started it would BEEP and display the service parking brake indicator. It goes away after restarting the car the first time (although, if the warning was on when you shut the car off, next time you get ready to start the car the warning light in the brake control switch is on, it comes on the moment you press the unlock button of the key-fob), but then comes back after driving for a while. Sometimes on the gas, sometimes on the brake, sometimes just coasting down a hill, sometimes just setting at a red light. The first few times it appeared it seemed like it was at roughly 50-60 mile intervals, but that has been decreasing over the couple weeks I've been getting it. That is why it's led me to believe the pads triggered it.
If anyone has the TSB number handy that joegr is referring to, I'd really appriciate it.
Rifleman@LaymansPC.com
Well-Known LVC Member
No clue as to why, but I had to toss the wheels on the car and drive it this evening (before getting into tearing doing the brakes) and drove it several hours with no service parking brake warnings.
Anyone know if the electronic parking brake uses the 5V circuit for any of it's modules or sensors? Anyone know how to retrieve DTCs from this system?
Anyone know if the electronic parking brake uses the 5V circuit for any of it's modules or sensors? Anyone know how to retrieve DTCs from this system?
joegr
Dedicated LVC Member
You can pull the codes from the parking brake module using a scan tool that has Ford specific codes enabled. One example (purchased with the Ford option) is AutoTap. I think the only connection between the parking brake module and the PCM is the CAN bus, so I wouldn't think the 5V sensor supply from the PCM would be a factor here.
I think the TSB # was/is 17673.
What you described above is an "AP", not a "MAP", so that does make sense.
MAP = Manifold Absolute Pressure.
AP = Atmospheric Pressure (aka barometric pressure).
Some cars have both (somewhat older ones), and others just have one.
I think the TSB # was/is 17673.
What you described above is an "AP", not a "MAP", so that does make sense.
MAP = Manifold Absolute Pressure.
AP = Atmospheric Pressure (aka barometric pressure).
Some cars have both (somewhat older ones), and others just have one.
Rifleman@LaymansPC.com
Well-Known LVC Member
All I have (at the moment) is an Actron CP9145. Don't think it's got all the ford specifc stuff in it.
Can't find anything on the TSB mentioned other than the fact it exists.
As for the MAP/Baro all being integrated with the MAF and IAT bit, I'm just parroting what the mechanic explained about the new units used on certain '03 and up Ford models. From my previous reading I've found that it's all intertwined in such a way that what he said doesn't seem too far fetched for me.
Not that I take wikipedia as the gold standard for information, but I've found nothing to contradict:
"The MAP sensor can be used to directly measure the BAP (barometric absolute pressure)."
and
"The BAP sensor is often located within the ECU, and the MAP sensor is usually located near the intake manifold."
Source> http://en.wikipedia.org/wiki/MAP_sensor#Barometer_and_vacuum_calculations_based_on_MAP
If Ford is now using a hybrid electronic MAF, MAP, and IAT rolled into one unit as he stated, I don't see why it's gotta be on the intake with certain BAPs being "often located within the ECU". It's something new, who says it's gotta work like the old stuff to do the required job?
Like I said before, maybe Maxx will pop in Moday with some extra info on the internals of the sensor. Would be nice,, I'm super curious at this point.
I was just out to provide the fact that a P0108 code that points to MAP Sensor Circuit High Voltage can actually be these funky new EGR valves with an EVP module on it. (For all I know that EGR/EVP module is where the MAP actually is and the mechanic at the dealership was being a typical stealership employee and trying to point me in the wrong direction so I'd give up and bring it in or was out to peddle crap that wasn't needed...)
Either or, NO MORE CEL for P0108 for me! Which is all that honestly matters to me.
joegr
Dedicated LVC Member
I think we're both saying more or less the same thing. As I said, I can understand the airflow, pressure, and temperature sensors being all built into the same assembly now. I'm just saying that it is an AP or BAP sensor, and not a traditional MAP sensor. To me (from the old days) a MAP sensor always measures manifold vacuum, not outside air pressure. It's possible however, that the definition of "MAP" has changed in recent years.
I do very much appreciate the information that those three functions are all now covered by the MAF (or at least that's what I would have called it). You never know when that will come in handy.
BTW, I do know by experience that a single bug on the wire of the MAF sensor will completely prevent the engine from running.
I do very much appreciate the information that those three functions are all now covered by the MAF (or at least that's what I would have called it). You never know when that will come in handy.
BTW, I do know by experience that a single bug on the wire of the MAF sensor will completely prevent the engine from running.