PCM reset methods??

Thanks for the clarification, joe! Maybe I'm feeling the throttle drop, but I swear it feels like the brake is on or the car perhaps is in a low gear, because as soon as I take my foot off the gas, it slows quickly.

Now I know my next step, get the codes!
 
If the parking brake were really on, you would get smoke from the rear brakes in a mile or less.
 
Yeah, I didn't see any smoke. I scanned for codes with my OBD Link module and my phone app. It said no codes were present. I'll see if one of the parts stores has a free Ford scan available.

There is no check engine light on and no other fault light showing on the dash at this time. Maybe I have to do a scan while the fault is occurring?
 
2005_LS_V8 said:
...There is no check engine light on and no other fault light showing on the dash at this time. Maybe I have to do a scan while the fault is occurring?
Click to expand...

It (they) should be stored even with the light off. It/they will be cleared if you go through enough drive cycles without the issue occurring, or if you disconnect the battery.
 
If the brakes were applied lightly by the PCM... a person might not see smoke, (also depends on the type of brake pads). This sounds like a wheel speed sensor which will lead to an ETC failsafe mode. Possibly a traction control issue which would cause applied braking. Most likely still a wheel speed sensor,,, or something within that system. If you want to be sure that brakes are not being applied,,, check for wear on pads... or blueing/browning of rotors caused by excessive heat. Check all 4 corners and compare each.
 
Parking brake being applied and main brakes being applied (via ABS) are two very different things. OP was talking about the parking brake.

(The PCM can apply neither. The parking brake is applied by the parking brake module. The PCM has no ability to command it to do so. The main brakes can be applied by the ABS module. It does communicate with the PCM, but it mostly goes the other way. The ABS module can command the PCM to reduce engine power. I do not believe that the PCM can command the ABS module to apply any of the brakes. The ABS module decides to do so on its own.)
 
Quote Joe:

"(The PCM can apply neither. The parking brake is applied by the parking brake module. The PCM has no ability to command it to do so. The main brakes can be applied by the ABS module. It does communicate with the PCM, but it mostly goes the other way. The ABS module can command the PCM to reduce engine power. I do not believe that the PCM can command the ABS module to apply any of the brakes. The ABS module decides to do so on its own.) "

I'm not saying that the PCM was applying the parking brake... but more that the PCM was getting some sort of readout to apply brakes due to a false sensing of wheel spin, (traction control). To me,,, this would go back to a wheel speed sensor having an intermittent false reading. I don't care what system commands what... but it seems that according to what 2005 is saying,,, something is telling his LS to apply the brakes... WITHOUT cutting power to the engine. This would seem to be an issue with the traction control part of the system, (falsely sensing wheel spin/slippage), which would most likely be a wheel speed sensor... or a fault within that part of the system.

IRRC... someone recently posted an issue with hearing a "beep" from the LS,,, and before they could look at the message screen... the fault went away. IRRC... you said you had experieced that too,,, and said that it was a fault that happened quickly enough that the OBD couldn't record the problem. I too have experienced that... and also remember another thread where somebody was having similar "quirks" with their LS,,, ansd suspected the idea of the battery being in the trunk... and over time the corroded spot welded chassis of the LS becoming a poor ground,,, and having the idea of running a ground wire from the battery directly to the engine.

If the afformentioned issues are part of the same problem,,, then the poster that suggested the ground wire may not be that far off. However... I will go a bit further to suggest "star grounding". This means tapping into the ground on each module,,, and mounting them to a central point that also grounds to the battery... rather than using the chassis for a common ground.

Hope the link works:

https://www.google.com/search?noj=1.....0...1c.1.64.serp..12.4.2334...0.f6LhSwineCM

If not... Google search "star grounding for electronics". It has worked for many applications over the years,,, but hasn't become a popular idea until recent years from what I understand, (like after the LS was manufactured).

https://www.google.com/search?noj=1....8.11.2475...0j0i22i30k1j33i160k1.8IdGKQspURM
 
Thanks all for the expert replies! Yes, it's been several drive cycles since the error, so that explains the missing code.

ABS/Wheel speed sensors/Grounding issues... This is good to know. I can definitely check all my cable connection points for corrosion. I'll take pics of the error message and get the codes next time it happens.
 
04_Sport_LS said:
...I'm not saying that the PCM was applying the parking brake... but more that the PCM was getting some sort of readout to apply brakes due to a false sensing of wheel spin...
Click to expand...

This is just not how it works! The PCM (Powertrain Control Module) controls the engine and the transmission. It has no control over braking of any sort. The ABS controller has control of the hydraulic brakes (all four wheels), and the parking brake module has control of the parking brakes (rear wheels). The ABS controller can command the PCM to reduce engine power, and the ABS controller tells the PCM how fast the car is going (this is needed for throttle control among other things). The PCM can command the parking brake module to release the parking brake. It can't command it to set the parking brake.

I don't get what your argument here is. I already said way back in this thread that his problem is very likely related to an issue with the ABS module or the wheel speed sensors. (Yes, the ABS could be applying brakes, but the PCM can not.) Bad car speed data to the PCM from the ABS will trigger a particular ETC failsafe mode. ETC failsafe makes the throttle anywhere from a little less responsive to completely non-responsive, depending on the exact cause of the failsafe. I'm sorry if that was unclear.

joegr said:
...A fault with the ABS (module, wiring, or wheel sensors) can trigger the following lights - ABS, AdvanceTrac or traction control (whichever you have), service-parking-brake (it gets upset if there is no vehicle speed info from the ABS), and ECT failsafe (also upset because there is no vehicle speed info), and can trigger check-engine....
Click to expand...
 
My car had a recent PCM flash and all of a sudden the "ECT Engine Failsafe Mode" came on the dashboard display! What do you suggest has happened and what should I do to fix this?
 
03Lspinks said:
My car had a recent PCM flash and all of a sudden the "ECT Engine Failsafe Mode" came on the dashboard display! What do you suggest has happened and what should I do to fix this?
Click to expand...

I replied to your other post on this with some questions about it. Do you really want help?
 
Joe,

Correct me if I am wrong... but doesn't the LS have a Yaw sensor along with the steeing wheel position sensor??? If either or both of these were faulty... wouldn't that cause applied braking to the rear???
 
04_Sport_LS said:
Joe,

Correct me if I am wrong... but doesn't the LS have a Yaw sensor along with the steeing wheel position sensor??? If either or both of these were faulty... wouldn't that cause applied braking to the rear???
Click to expand...

Yes, it does. If the AdvanceTrac were triggering, he would have a flashing AdvanceTrac light. Also, the AdvanceTrac would be telling the PCM to reduce power.

Why, is it so hard to believe that ETC failsafe is reducing throttle response instead? This is the likely reason, all the braking theories are much, much less likely.
 
I've been lurking these forums for about a year now, since I purchased my '02 LS v8. I have finally now had to make an account!

Sorry if I'm posting in a wrong thread but I've read so many ABS, traction control, wheel speed sensor threads that my f'in head is dizzy. ABS light and traction control light were on for about a month. Got the the point that I had to turn off traction control for my car to move, else it had very little power and felt like it was sputtering. Local Advanced Auto store read me my ABS codes showing front left and right speed sensors were bad. Took it to local Ford dealer to pinpoint what the problem really was. They raped me $125 to tell me my LH front sensor wasn't reading anything and my RH front sensor was on its way out. Wanted $360 for parts and labor on replacing front LH sensor, $505 for both front LH and RH sensors.
Obviously, I went to AutoZone and picked up 2 brand new ones and installed them myself.

Started vehicle, and my ABS and trac control lights were still on. Backed out of driveway then drove about 30-40 feet and the ABS light shut off but the trac control light stayed on. Pulled back in to my driveway and disconnected the battery with the key in the on position in hopes that it would clear a soft code of some sort.

No luck. Traction control light is still blinking on my dash. When I drive, it does feel like one of my rear brakes is slightly being engaged partially for a split second per wheel rotation.
I am able to push the traction control button next to my cup holders and turn them off and on but the blinking light still remains. Really don't want to go back to the dealer. I feel violated with the prices they tried to throw at me lol.

Sorry for the winded post. Hoping not to have to post much unless its something helpful and less about problems!
 
NickyCapo said:
I've been lurking these forums for about a year now, since I purchased my '02 LS v8. I have finally now had to make an account!

Sorry if I'm posting in a wrong thread but I've read so many ABS, traction control, wheel speed sensor threads that my f'in head is dizzy. ABS light and traction control light were on for about a month. Got the the point that I had to turn off traction control for my car to move, else it had very little power and felt like it was sputtering. Local Advanced Auto store read me my ABS codes showing front left and right speed sensors were bad. Took it to local Ford dealer to pinpoint what the problem really was. They raped me $125 to tell me my LH front sensor wasn't reading anything and my RH front sensor was on its way out. Wanted $360 for parts and labor on replacing front LH sensor, $505 for both front LH and RH sensors.
Obviously, I went to AutoZone and picked up 2 brand new ones and installed them myself.

Started vehicle, and my ABS and trac control lights were still on. Backed out of driveway then drove about 30-40 feet and the ABS light shut off but the trac control light stayed on. Pulled back in to my driveway and disconnected the battery with the key in the on position in hopes that it would clear a soft code of some sort.

No luck. Traction control light is still blinking on my dash. When I drive, it does feel like one of my rear brakes is slightly being engaged partially for a split second per wheel rotation.
I am able to push the traction control button next to my cup holders and turn them off and on but the blinking light still remains. Really don't want to go back to the dealer. I feel violated with the prices they tried to throw at me lol.

Sorry for the winded post. Hoping not to have to post much unless its something helpful and less about problems!
Click to expand...

So, the dealer charged the rate that they said they would, and told you what was wrong (which you already knew), and now you are upset with them. What did they do wrong?

Dealer rates for parts and labor are high. Everybody knows that. It is what it is. Note that they likely were going to replace the front hubs (which come with the sensors), and not just the sensors.

Going to a dealer is rarely the right answer for a car that is 15+ years old.

Your remaining problem might be one or both of the front hubs. They are a part of the ABS sensor system. Alternately, it might be another problem that was undetectable till the other sensor problems were resolved.

You need to get the codes read again to see what is being reported now. (This assumes that you really want to fix this, rather then just complain.)
 
Hey, thanks for the prompt reply.
I was lightly joking about the dealership and how expensive they are. Yes, I knew how much it was going to cost when I called and made my appointment. I was only pointing out that I paid them to confirm basically what I already knew and that I'd rather not pay them anymore money. I understand it's hard for people to determine tone when reading something online.

If they intended on replacing the hubs, then that was not disclosed to me by the technician when discussing his findings and his solution to the dead sensor(s).

Clearly, I would like to have my problem resolved, which is why I made an account and reached out on this forum.

I debated buying 2 new hub assemblies as I see that they come with the sensors but since the dealership made no mention of them yesterday, I opted not to purchase them. I will take a drive up to the local parts store to see if they can pull some codes for me. I was unaware that the traction control light alone would throw a code.
Thanks for your help. Apologies if there was misunderstanding in my tone and intentions.
 
It will. In fact, if they had a Ford specific scanner, it would pull several other complaint codes that you don't know are there.

You might consider investing in Forscan if you plan on keeping this car. It's a really cheap way to get to all the codes without having to go to the store and wait for them to pull them.

So, do you have traction control, or AdvanceTrac? (Spinning wheel symbol or sliding car symbol?)

Traction control is just some more software in the ABS module. AdvanceTrac is more software plus more hardware (codes still come from the ABS module).
 
The only light that I have on my dash now is: Orange in color, top middle, slightly to the right; car with 2 squiggly lines underneath it (sliding car symbol I assume).

I will look into Forscan. I was actually looking for a decently priced scan tool for my LS and if Forscan will work, and is reasonably priced, I will gladly purchase it.
 
The most common AdvanceTrac issue (that does not also turn on the ABS light) is the steering angle sensor. The 2nd is the yaw sensor. Of course, there are a few more possibilities beyond those.

I have not tried Forscan, but I have heard from more than one source that it does everything my $400 tool does.
 
My research has also yielded those two problems you just mentioned: steering angle sensor and yaw sensor. Is it possible the steering angle sensor could be bad even if my horn and other steering wheel buttons are working as they should? I've seen people reporting airbag lights, bell continuously ringing and other issues like that when the steering sensor has gone bad.

So Forscan can basically tell me everything that the Ford/Lincoln dealership would charge me to diagnose, is what you're saying? Because if so, thanks a million because I have never heard of Forscan until now and have been tirelessly scanning through Amazon for the best Scanning tool at the most reasonable price for days now.
If Forscan isn't as descriptive as the dealership, would it atleast tell me why my AdvanceTrac light ( thanks for the correction ) is now blinking?
 
NickyCapo said:
My research has also yielded those two problems you just mentioned: steering angle sensor and yaw sensor. Is it possible the steering angle sensor could be bad even if my horn and other steering wheel buttons are working as they should? I've seen people reporting airbag lights, bell continuously ringing and other issues like that when the steering sensor has gone bad....
Click to expand...

You, or the threads that you read, have gotten pretty confused here. Those are two very separate items.

1. Steering angle sensor is under the dash, near the firewall, on the steering column. It reports the angle that the steering wheel is turned to. It affects only the the AdvanceTrac, and does no other functions.

2. Clockspring is on the steering column, just behind the steering wheel. It makes all the needed connections between the steering wheel (which rotates) and the steering column (which does not). It affects the button lighting on the steering wheel, cruise control switches, radio switches on the steering wheel, the horn button, and the driver's front airbag.


NickyCapo said:
...So Forscan can basically tell me everything that the Ford/Lincoln dealership would charge me to diagnose, is what you're saying? Because if so, thanks a million because I have never heard of Forscan until now and have been tirelessly scanning through Amazon for the best Scanning tool at the most reasonable price for days now.
If Forscan isn't as descriptive as the dealership, would it atleast tell me why my AdvanceTrac light ( thanks for the correction ) is now blinking?
Click to expand...

No, it does not do everything that the dealer tools can do. For example, it can't reFLASH the PCM or alter the door code, and a whole bunch more stuff like that. These are things that you can't do without a yearly subscription to Ford anyway. Certainly, my tool (autoenginuity) can't do that either.
 
My apologies. To clarify: my research on this forum, and other places online, have yielded those options as possibly being my problem. Yes, I confused steering angle sensor with the clockspring (I've done a lot of reading the past week).


I've been looking for a good Bluetooth scanner since you've mentioned Forscan. I hope the OBDLink MX to be sufficient. I'm hoping my issue ends being something I can do without the help of the dealership and their specialty tools.

Going to auto store now to hopefully get a code for this blinking light to start somewhere. I will definitely post my findings. You've been super helpful, thank you.
 
Ok, so I went to Advanced Auto. Their little reader brought up the front 2 sensors (C1233, C1234) even though my ABS light disappeared after replacing them. The guy said that it was probably just 'history codes' and I haven't driven enough for them to clear out of the system. This is all new to me so I don't know if that's true or not. If it is, I don't understand why the ABS light would be off but still throwing the codes. I decided to take the highway home (just one exit and a little further) to see if anything would change. I did notice that my cruise control didn't work. When I got off the highway, I pulled over and shut my car off and then restarted it. I then reached a high enough speed and my cruise control started working, which was kind of weird. And still have blinking AdvanceTrac light.
 
Any history should have been cleared when you disconnected the battery.
It could be that the hubs are bad. It could be that the aftermarket sensors aren't good enough.
It could be the wiring between the ABS module and the sensors.
It could be the ABS module.

None of this really makes adds up as this should have your ABS light on too.
I'd want to be sure with a good scan tool. I'd scope the front wheel speed signals.
 
The sensors are Duralast brand from autozone. Since you mentioned Forscan earlier, I've been doing a lot of research on finding a good bluetooth tool to use in tandem with it. It looks like Forscan should be a good enough scan tool to help me figure this thing out, right?
I stumbled across another thread and you had all the answers in that one, too (doesn't surprise me) and it mentioned a calibration?
 
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