HP Tuners for 2005-2015

Unfortunately the Toyota flashing routine is one of the least robust of all manufacturers. Most communication or connection errors result in a bricked PCM. Not much can be done about it i'm afraid.

 

You can see how the throttle opens gradually and dips a few degrees.
Again I'm just experimenting to see what happens...
With the modified map the throttle opens faster, a few degrees more and stays open...
I modified both maps and now I'm going to put the low load map closer to stock..
I made drastic changes and truck drives basically the same.... except the cruise control...

Well this map is used as a torque limit for the traction control, because now my traction control doesn't kick in.
So we can fine tune our traction control... Still working....

 

yeah she is done. any particular reason why it failed like it did? there is no CAN communication now.
I have VCM Editor version 4.4.4

 

if you create a ticket and include your debug.dat file from /documents/hp tuners/settings it will tell me what happened. Most likely there was a glitch on the CAN bus and the communications timed out. Sometimes if you unplug the MPVI2 from the truck and the PC then connect it back up again it may recover, but often the PCM won't reset the CAN bus correctly without a reset. Unfortunately as soon as you cycle the key, disconnect the battery etc. the PCM is bricked.

Most other manufacturers have a "boot" section of the flash chip that is never erased or overwritten so the controller can almost always be recovered after any failure. Also, many other manufacturers split the flash into Operating System and Calibration sections that are erased and written independently (this also means much faster writes if you only change the calibration). Unfortunately Denso didn't take either of these approaches and the entire flash chip is erased and written.

 

well thats some shit.. Makes me a bit worried to flash the TRD SC tune HPT after it. Hopefully that does not plague me or may need to pick up a spare ECU before hand. Not ideal.

 

High percentage of success. Don't over worry yourself.

 

It's almost always a battery voltage issue, really are scenario

 

Interesting. Over- or under-voltage?

 

Under voltage is the biggest concern usually. Even with the OVtune flash, you shut off all unnecessary battery draws to help maintain a higher voltage. I picked up a voltage booster few months back that retains the fuse. So far so good with about a 0.5V boost.

 

Thanks for confirming! Implies those of us with AGM batteries and associated voltage boosters may be somewhat protected, especially when connected with an external charger while flashing.

 

I use this when I do flashes at work. A little overkill for the DIY guy at home, but they are able to maintain a very stable voltage, even on the more accessory-packed vehicles that draw big power when the key is on.

$503 Schumacher Electric DSR ProSeries INC100 Fully Automatic Battery Charger and Flash Reprogramming Power Supply with Service Mode, 100 Amps, 12 Volts, Black, 1 Unit

https://www.amazon.com/Schumacher-INC100-Battery-Charger-Supply/dp/B0756NVGHV

 

@HPTuners, is there anyway to precheck CAN connections to the truck via the MPVI2 before flashing to make sure things are all good? (Like connect in vcm scanner? or "read" the cal file in vcm editor?)

Correct, like stated i have flashed probably 30+ times, no issues, but I always go through a very strict procedure of making sure everything is off and in order before clicking the big red button. I guess the only thing i might be missing is a voltage readout of the battery.

 

Maybe read the current cal before you attempt a write? Not a fail-safe, but maybe just a reasonable "feel good".

 

This is great info. Another reason to replace my original 5+ year old battery with an AGM before winter and not flash tunes while on the road right now. Was going to ask for nd4spd's v10 tranny tune before I drive back to Colorado but think I'll wait.

So sorry it happened/bricked to a few of you, though. What's the course of action now? Junkyard?

 

Yeah, I might have to rethink flashing in the parking lot of work now haha.

what are peoples thoughts on popping the truck on say a battery tender while flashing? I wonder how much amp draw is on a truck with all lights and accessories turned off and ignition on?

 

This was my thought as well, or hooking up a jumper pack or something.

 

This is curious. I wonder what your throttle blade angles are during this. There are so many "throttle % numbers" that can be recorded during everything, but i dont think i have ever seen them dip like that during WOT pulls. Here are two screen shots from this mornings logging. First a cruising speed, second at WOT, notice WOT none of them dip. Realistically, Accelerator pedal % (how far the actual gas pedal is pushed down) and Throttle [desired] angle (how far the throttle blade is open) are the main ones to look at, and they act as intended, the other ones... who the hell knows.

Cruising:


Wot:

 

anything under 12.1 volts I wouldn't even attempt a flash

 

Ordered one off ebay

Toyota tells us to hook up to out charger/test to supply a consistent 13.5V. Prob should order a charger for home for this next round.

At work our general rule is as long as it's above 12.5V for a short update, haven't had a problem untill now

 

Couple of questions around this, maybe directed @HPTuners - do you have to buy 4 more credits now to flash your replacement ECU?

Also - around the immobilizer - is this something you can sort with techstream? @JustDSM had made some comment about using a paperclip - what's the deal with that?

In the past I liked to keep a spare ECU around - just trying to gauge what would be involved cost and effort wise to switch to my backup.