Can read but can't write to PCM

[Mrmaroon]

Hey guys! i'm new here, i have a few questions about writing a new tune. I put in a 160 thermostat and need to lower fans. I edited my bin (has to be a stock bin) in tunerpro RT. I changed the fan thresholds from 107 and 113 to 90 and 100. The car gets really hot in traffic (230F on datamaster) and since it leaks oil it smells really bad. My fiance won't ride with me anymore!

I'm running into problems when I try to write the bin to the PCM. I can datalog with datamaster/9495scan/tunerpro just fine. I can read my bin with winflash about 75% of the time. When I go to write it erases the old settings then as it starts to write it says "INCORRECT MESSAGE SENT". Then it shuts down. I'm using a laptop with Windows 8.1. I installed it in compatibility mode for XP (S3) and run as administrator. The cable is a red devil river one.

I've tried researching this, but there isn't a lot of info on winflash or writing failures in general except for bricking. Hope someone can help :confused:

[SSlowBoat]

Hmmm, I never used winflash. I always use cats tuner to flash. Most issue I get from that program is security error when it starts to write then it fails, usually happens if I have any other datalogging/tuning programs open. I usually exit the program entirely, turn off and pull key, open close drivers door, then try again.

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[MoeHorsePower]

Try pulling the pcm fuse on the drivers side panel, turn on the ignition and let it go through its security cycle, key off, and put the fuse back in, sometimes the pcm gets into a frozen state...

[zoomo]

Does the car still start? So you know its not bricked? Lol.

Mine wont work with the aftermarket gauges plugged in. They are hooked into the spare fusebox ignition spot. But for some reason it errors when they are connected most of the time. Just a thought.
I also have one computer that I can only read but not write. Not sure why, it may be a flaw in the particular computer.

[Mrmaroon]

I tried a few things last night. I unplugged all the fan relays and the abs relay. I changed some settings on my com port. It still wouldn't work. Then when I tried to fire it up it would run for 2 seconds and die with the fans on. I left it unplugged last night and now it's driving again. The flasher never even gets to erasing the bin now. It craps out pretty fast.

I might leave this one alone for a while! I don't have another set of wheels.

[zoomo]

Kinda made my heart drop for a second reading that description . if it starts and dies or doesn't start that's a bad sign. also if your fans come on when the key comes on that's a bad sign.

Since its starting now though it seems you're in the clear. For future reference, I'm not sure how true this is, buy I have bricked a couple computers so I will follow this rule if ever having problems again.

If it ever fails during writing, remove the pcm fuse before hitting OK on the computer or turning the ignition switch off. This is supposed to possibly save it? I don't know. But its worth a try if it ever gets stuck. Sucks to lose one.

Good luck man, keep us updated. I struggled with mine for a while

Edit: also I think mine would do what you're saying if I errored it out when reading, but the two times it errored while writing it killed it. I didn't do that fuse trick either time though so I'm not sure if it works.

[roughneck427]

Ive never had any good luck with any of Tunercat stuff in anything but windows xp. My obd1 and obd2 TC I run in windows XP virtual mode and do not have any issues. I have bricked a couple even installing the program per the instructions of compatibility mode and admin.

[Mrmaroon]

Ive never had any good luck with any of Tunercat stuff in anything but windows xp. My obd1 and obd2 TC I run in windows XP virtual mode and do not have any issues. I have bricked a couple even installing the program per the instructions of compatibility mode and admin.

I was wondering if I could run it in xp with a virtualization software like VMware. Is this what you mean?


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[Mrmaroon]

I downloaded VMware and got a copy of windows XP x86 from Purdue. Can't believe how easy this was to set up. They have really improved VMware. My Internet worked without even going to settings and the cable was recognized too. I installed drivers manually for the cable, somewhere I read that the auto-drivers can block the chinese adapter. I guess its an illegal adapter they sell on ebay.

I'll do 3 reads and pray for the LT1 gods favor!

Edit: Did my 3 reads just fine. Went for the write and same problem :( . It establishes communications, erases flash memory, then I get "Incorrect Message Sent". This time my car started up ok again though.

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[LDM]

Could be a grounding issue. You can try grounding the laptop to the chassis. I remember some people used to have issues with this on the older serial style OBD1 interfaces.

Another thing to check would be the wiring and the OBD connector on both the car and the adapter. Perhaps you have a short somewhere that's causing an issue.


It might also be an issue with the PCM. Its rare but could be that the FLASH memory has a failure to the erase mode and can't erase the chips. If so you would be able to read but never write to them. Might want to try another PCM just to be certain.

[firebird_1995]

The chips that are used in these PCMs will allow the computer to be read all the way down to 5 volts, however during the programming process it requires a minimum of 12 volts or it will shut down. Make sure your system voltage is above 12 volts and try it again. A word of warning though, if the process goes far enough and actually erases the chips and something were to happen you will not be able to start it. The PCM will be bricked

[Mrmaroon]

The chips that are used in these PCMs will allow the computer to be read all the way down to 5 volts, however during the programming process it requires a minimum of 12 volts or it will shut down. Make sure your system voltage is above 12 volts and try it again. A word of warning though, if the process goes far enough and actually erases the chips and something were to happen you will not be able to start it. The PCM will be bricked

How should I check the voltage? Use a tester on the battery or just look at the gauge ?


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[firebird_1995]

I would use a voltmeter on the battery. The gauge on the dash may not be accurate

[LDM]

The chips that are used in these PCMs will allow the computer to be read all the way down to 5 volts, however during the programming process it requires a minimum of 12 volts or it will shut down. Make sure your system voltage is above 12 volts and try it again. A word of warning though, if the process goes far enough and actually erases the chips and something were to happen you will not be able to start it. The PCM will be bricked

Another good one that I forgot about. A weak battery that isn't holding a good charge can cause all sorts of problems both reading and writing.

[Mrmaroon]

Ok, I will get a new battery. This one is probably bad. I bet it sat for a while before I bought the car.

[mdw95TA]

I got the exact same problem with my RDR cable. Waiting on a Moates cable to arrive, I will post results. From what I been reading this is quite common with these RDR cables.

[Mrmaroon]

I got the exact same problem with my RDR cable. Waiting on a Moates cable to arrive, I will post results. From what I been reading this is quite common with these RDR cables.

Thanks ! Let me know. I found out my battery wast installed in 2009. They didn't mark it except for the receipt I found when I pulled it! I'm going to change it and check again first.


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[mdw95TA]

I will let you no forsure, might be a week or 2, slow shipping to Newfoundland.

[mdw95TA]

Got my new Moates cable today, it worked perfect. Done my first flash, no more errors. Must be a bad batch of RDR cables.

[Mrmaroon]

Got my new Moates cable today, it worked perfect. Done my first flash, no more errors. Must be a bad batch of RDR cables.

Ok, thank you!


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