PCM reset methods??

[RAPHAELJUNIOR]

i had to reset my car (03 LS V8) so i disconnected the neg. for 48 hours. it did reset it ok. point is, does this method (discon. battery) entirly reset the pcm 100%? or does the dealer have methods that reset/reflash the pcm 100% if so what are the methods and how much would it cost? i think i have a bug in mine.

 

[ToddG]

I do not believe it resets the PCM entirely. The PCM contains software and firmware that is not changed unless it is done by the dealer.

On the other hand, when you disconnect the battery, the adaptive controls for (1) the idle/fuel trim strategy, and (2) the transmission shift strategy, are wiped. These two strategies must be relearned by the PCM. Here's what the Owner's Manual says about this:

Because your vehicle’s engine is electronically controlled by a computer,
some control conditions are maintained by power from the battery. When
the battery is disconnected or a new battery is installed, the engine must
relearn its idle and fuel trim strategy for optimum driveability and
performance. To begin this process:
1. With the vehicle at a complete stop, set the parking brake.
2. Put the gearshift lever in P (Park), turn off all accessories and start
the engine.
3. Run the engine until it reaches normal operating temperature.
4. Allow the engine to idle for at least one minute.
5. Turn the A/C on and allow the engine to idle for at least one minute.
6. Drive the vehicle to complete the relearning process.
• The vehicle may need to be driven to relearn the idle and fuel trim
strategy.
• If you do not allow the engine to relearn its idle trim, the idle
quality of your vehicle may be adversely affected until the idle
trim is eventually relearned.
When the battery is disconnected or a new battery installed, the
transmission must relearn its adaptive strategy. As a result of this, the
transmission may shift firmly. This operation is considered normal and
will not affect function or durability of the transmission. Over time the
adaptive learning process will fully update transmission operation to its
optimum shift feel.

Why do you think you have a bug? Are you aware that there is a firmware update for the 2003 LS PCM to address harsh shifting issues?

 

[RAPHAELJUNIOR]

I do not believe it resets the PCM entirely. The PCM contains software and firmware that is not changed unless it is done by the dealer.

On the other hand, when you disconnect the battery, the adaptive controls for (1) the idle/fuel trim strategy, and (2) the transmission shift strategy, are wiped. These two strategies must be relearned by the PCM. Here's what the Owner's Manual says about this:



Why do you think you have a bug? Are you aware that there is a firmware update for the 2003 LS PCM to address harsh shifting issues?

i think that i have a bug because im always getting "etc engine failsafe mode" and the check engine light and i get LIMITED throttle usage. i have replaced the throttle body the MAFS and the thermostat and still the error messages. im lucky to drive 5 mile with out throwing codes. apparently the dealer said the K&N kit i had started the problems but i doubt it that is too big of a problem, plus ive been drive with the stock intake and i still have the same problems. no i wasnt awar of the firmware update thanks for the info!!

 

[ILLS]

When resetting the PCM all that does is reset the KAM (keep alive memory) which controls such things as LTFT (long term fuel trims) as well as a few other things.

To do a proper PCM KAM reset you should disconnect the battery and then tap the brake pedal a few times to ensure total discharge of entire system. Wait a few minutes and then reconnect the battery.

 

[eastcoastLS]

are there any PCM updates for the 2000 LS PCM?

 

[SoonerLS]

i think that i have a bug because im always getting "etc engine failsafe mode" and the check engine light and i get LIMITED throttle usage. i have replaced the throttle body the MAFS and the thermostat and still the error messages. im lucky to drive 5 mile with out throwing codes. apparently the dealer said the K&N kit i had started the problems but i doubt it that is too big of a problem, plus ive been drive with the stock intake and i still have the same problems. no i wasnt awar of the firmware update thanks for the info!!

A "bug" in the firmware is possible, but it's not likely. The first thing you ought to do is take COP #4 and swap it with #1. COP #4 is close enough to the PCM that the RF interference it radiates when misfiring can trigger false error codes; the ETC Failsafe is the most common false code that's thrown in this situation.

Limited throttle in ETC Failsafe is normal; when the engine can't trust the ETC (Electronic Throttle Control), it can't control the engine, so you basically get the engine to idle, and that's it. It's a Safe Failure mode.

 

[RAPHAELJUNIOR]

A "bug" in the firmware is possible, but it's not likely. The first thing you ought to do is take COP #4 and swap it with #1. COP #4 is close enough to the PCM that the RF interference it radiates when misfiring can trigger false error codes; the ETC Failsafe is the most common false code that's thrown in this situation.

Limited throttle in ETC Failsafe is normal; when the engine can't trust the ETC (Electronic Throttle Control), it can't control the engine, so you basically get the engine to idle, and that's it. It's a Safe Failure mode.

so let me get this right, ignition coil #4 is on the passenger side toward the end/the last one right? if thats it i already tried that swap and had no luck. thanks good info though.

 

[03Lspinks]

I do not believe it resets the PCM entirely. The PCM contains software and firmware that is not changed unless it is done by the dealer.

On the other hand, when you disconnect the battery, the adaptive controls for (1) the idle/fuel trim strategy, and (2) the transmission shift strategy, are wiped. These two strategies must be relearned by the PCM. Here's what the Owner's Manual says about this:



Why do you think you have a bug? Are you aware that there is a firmware update for the 2003 LS PCM to address harsh shifting issues?

HOW DO I GET THE FIRMWARE UPDATE? I just had my tranny fixed and PCM replaced(actual issue). 2 months later it is doing the harsh shifts again out of nowhere. It idles rough in the morning. Could that be an issue with the exhaust?

 

[ycunderground]

Your pervious issues was the same problems I had. I replace oem coils, throttle body, egr / map sensor, tps and so on. Sent my pcm out for repair and it correct my problem. As for an firmware update you would have to visit your local ford / lincoln dealer to reflash your pcm. Hopefully you will get a tech that knows how to properly flash a pcm and not corrupt the data or brick your pcm.

 

[grizzlyls]

If your PCM was brand new from Ford, then you would have the last flash, unless they sold you really old stock. In those cases, use Ford warranty. If as I suspect you bought used/rebuilt, then you may have swapped bad for bad. SIA electronics is what all use here for PCM repair, and seems to have never been an issue after. Search thread or google for link.

When I talked to dealer about doing a flash, they acted like its likely for it to damage the PCM. After research what I found, is that what the real problem is a mech that doesnt know the right way of a very strict procedure. Of course, then the dealer doesnt want to eat a new PCM (over 1k) so they blame the 'old' when its really not. If I ever get to that point on my 2001, I will get the estimate to say that the dealer will eat it if something goes wrong. Which probably means none will touch it lol.

 

[BigBalla39213]

If your PCM was brand new from Ford, then you would have the last flash, unless they sold you really old stock. In those cases, use Ford warranty. If as I suspect you bought used/rebuilt, then you may have swapped bad for bad. SIA electronics is what all use here for PCM repair, and seems to have never been an issue after. Search thread or google for link.

When I talked to dealer about doing a flash, they acted like its likely for it to damage the PCM. After research what I found, is that what the real problem is a mech that doesnt know the right way of a very strict procedure. Of course, then the dealer doesnt want to eat a new PCM (over 1k) so they blame the 'old' when its really not. If I ever get to that point on my 2001, I will get the estimate to say that the dealer will eat it if something goes wrong. Which probably means none will touch it lol.

I doubt Ford had a new one. I tried about a year ago to find one for a customer with no luck. As for Flashing...all you need to do is find someone with a J2534 Pass Through Device. If you lived close by I would do it for free or whatever the Subscription cost.

 

[RigsLS]

HOW DO I GET THE FIRMWARE UPDATE? I just had my tranny fixed and PCM replaced(actual issue). 2 months later it is doing the harsh shifts again out of nowhere. It idles rough in the morning. Could that be an issue with the exhaust?

Your coils are failing.

re&re all OEM coils and NGK iridium plugs correctly gapped, change the air breather element, clean the MAF sensor and replace the fuel filter, run STP through the tank. It'll shift fine when the misfire is fixed.

 

[03Lspinks]

CAN YOU EXPLAIN:
re&re all OEM coils and NGK iridium plugs correctly gapped?
change the air breather element?
clean the MAF sensor?

I'd appreciate it man. Ill do all of this on Monday!

 

[RigsLS]

03 V8 ???

re&re just means remove and replace.

V8 takes all brand new OEM Ford DG529 coils, they come with new fresh boots.

Before you pull the old plugs out, inspect deep down the plug wells around the bottom of the plugs for water or oil. If so you need valve cover gaskets and plug o-ring seals.

NGK Irridium's are good quality plugs and work best on this LS. They come pregapped but you need to double check every single plug and ensure its set to .040mm. Use feeler gauges for most accurate results. Don't damage the firing probe.

Put a good glob of dielectric grease inside the end of tip of the boots where the plugs seat.

Ensure you are gentle with all the coil connector and make sure you hear and feel the click as you reconnect them back up to your new coils.


Air breather element is just your air filter. Change it and inspection your entire plastic air intake snorkel even past the MAF all the way up to the throttle body, for any cracks or any misalignments at the clamps. You can't have any unmetered air coming in past the MAF. It'll throw off the air fuel mixture which the PCM can't adjust for as its past the MAF already.

MAF is your Mass Air Flow sensor, it's just west up the intake snorkel from the air filter, has a connector on it. It can be removed for cleaning. You'll find dedicated air flow sensor cleaner spray in the stores, gently spray it and don't touch the thin hair like sensor wire in the middle.

I'd disconnect the battery terminals while doing this so called tune up. On restart the PCM will go looking immediately for new air fuel mixture values. It'll do this on idle in seconds. It will also then need to relearn your adaptive shift strategy, just drive it the way you always do and it'll figure it out over time and adjust for optimum shift points.

Fuel filter really should be replaced, it's located inside the front drivers wheel well, easy, cheap and part of doing the above mentioned work. They get gunked up pretty good after many years. Immediately improves throttle response and milage. Spares the fuel pump from overworking.

When you have it out, try holding it upside down allowing it to drain the fuel within it out backwards into a bin or jar, have a look at how brown the crap that comes out looks like.

Good idea to change out your cabin air filter also. Cheap and simple ... provides fresh results to the interior.


GLWR



EDIT ---- not .040mm but rather .040in

 

[04_Sport_LS]

Not saying anyone else is wrong...

But are you getting and ABS or traction control light/warning also??? Interestingly,,, after reading through this forum in the last few days... a number of people have had "failsafe mode" problems due to wheel speed sensors being faulty. Not saying this is your issue,,, but something to consider

 

[03Lspinks]

Awesome explanation! I got all the parts you said! My plugs are 'Motocraft' & and my coil on plug boots are 'Autolite'! I'm sure or atleast I hope they will be fine! Going to take to my mechanic tomorrow in the AM then head to the gas station and add the STP! Hope the PCM can figure out and go back to normal. Will let you know what happens.

Thanks again bruh,

C

 

[02LincLS]

 

[RigsLS]

Whoops, not mm

good catch 02, thanks!

 

[03Lspinks]

Got the car back! Runs same for now, however he didn't disconnect the battery terminal! Was nervous it would reset some other stuff!
How long do you think the harsh shift will continue or do I need to disconnect the battery???

 

[joegr]

Disconnecting the battery will not mess up anything else on the car.
Disconnecting the battery probably won't help with your harsh shifts either.

 

[RigsLS]

... It idles rough in the morning ...

Get it running right first, only then look at any possible trans issues. PCM may need rework, Shift solenoid pack may need to be replaced. Fresh filter and fluid.

Disconnecting the battery initiating it to relearn the adaptive shift strategy parameters, is merely a 'feel good' effort but brings it back to where it should be.

Fresh coils, plugs and filters, verifying no vacuum leaks and resetting the PCM, if harsh shifts persist it means it's time to dig deeper.

May be wise to have it checked for fluid level and or leak before splurging on a reman.

We've seen guys replace all sorts of parts and shifting issues only resolved after the PCM was send out for repair.

It's a tough gig with these aging LS'es. I apologizes if I've steered you wrong but I'm convinced one should always make sure it's running correct before attempting to resolve shifting issues. No sense looking at possible trans issues if it's misfiring.

 

[03Lspinks]

Its all good man. I NEEDED that work done none the less. So resetting the PCM can only be completed with a scan tool or what not?

 

[joegr]

Its all good man. I NEEDED that work done none the less. So resetting the PCM can only be completed with a scan tool or what not?

Sorry if the answers weren't clear.
You can reset the PCM by disconnecting the battery and reconnecting it after a few minutes.
"Resetting" the PCM is very unlikely to correct the problems that you have.
Please go ahead and do it, so that we can stop talking about it and move on to possibly getting things fixed.

 

[2005_LS_V8]

I started having the ECM Failsafe error recently. It seems to engage my emergency brake at the same time; traction control light and the brake light on the center console are both lit up. I have the ability to accelerate, but the brake is on and of course cannot be disengaged while this is happening. Frustrating. I've had my software updated at a dealership before, the guy seemed to know what he was doing. That was about 2 years ago.

I have an extra vehicle, so I guess I could send mine off for repair if this continues. It's happened twice in the last 6 monts, but never before that. After sitting overnight, the problem is gone the next day.

 

[joegr]

...It seems to engage my emergency brake at the same time....

Nonsense!

The red brake light comes on for other reasons than just the parking brake. (Low brake fluid being the main one.)
The yellow light "service parking brake" light on the switch on the center console does not mean that the parking brake is applied, only that something is wrong with the system. (It usually means that it may not be able to apply the parking brake.)
It's "ECT" (Electronic Throttle Control) failsafe, not ECM failsafe (there is no such thing). ECT failsafe alters throttle response.

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.

I'd get the OBDII codes (need a Ford specific scanner that does ABS codes), and follow the troubleshooting flowcharts from there.