Tried SCT tune, failed, no-start, PATS 16, no OBDII communication

FDR

Dedicated LVC Member
Joined
Jan 20, 2014
Messages
2,041
Reaction score
168
Location
Central NJ
I'm currently under the assumption my PCM is fried. What is left to check?

2002 V8. I ran it for 20 minutes before starting the upload (car was off, of course)

I tried to load up Unleashed tunes from a brand new SCT X4, but it froze in the middle of loading a tune (I gave it an hour to make sure it wasn't changing). Of course, now that I have various problems to describe my situation, I've learned lots of fun things about how sensitive these tuners are to voltage changes and other hiccups to the point where they have a way to create a recovery tune from your stock tune saved filed

Now, the car won't start. It cranks, but won't fire. I don't hear the fuel pump. The PATS light is flashing 16. Check Advancetrac is displayed. My phone+torque and my computer+forscan are both failing to connect to the car through either of my OBDII bluetooth adapters. I have a cabled adapter on the way, but the BT ones I have now link up in seconds to my other car

I checked all the fuses and relays my owner's manual labeled as PCM, checked the passenger OBDII fuse, and checked the contacts on the SSP relays. The fuses have continuity (removed and checked) and the relay sockets were clean (didn't check functionality). I see 7 pins looking into the OBDII port, so I don't see it being as simple as a dislodged pin. The port powers the OBD adapters

I haven't checked the PCM wiring yet, but I have my obvious reasons for not expecting to have a eureka moment. I expect to pull it tomorrow or the next day to get the p/n in the least

So, have I exhausted all my options? Because this is a pretty major mood killer considering I had a trip planned for this weekend in this car
 
I swapped [Relay 14: PCM Power] and [Relay 15: Starter]. No change, no surprise

SIA is definitely a possibility. I'm going to call SCT shortly to see what they have to offer since the tuner is already married and the tunes are strategy and/or vin locked. Some cases have had the person send their tuner and PCM to SCT for their own testing, though I don't know if they have the ability to test an LS. I'm looking around at PCMs in the event the processor is fried, based on a Powerstroke thread that concluded with SIA saying a microprocessor was fried and was irreparable.

What is the difference between all the Gen 1 V8 PCMs that seem to come up as compatible? Ebay p/ns are all over the place, or course, and I can't find it by vin on Parts.Ford.com . All Computer Resources Inc has over 20 suffixes available, plus even more for the V6. I know I have to pull mine for the existing p/n, but it just seems crazy to have multiple versions vs just superseding revisions

All COmputer Resources:
Lincoln LS PCM ECM ECU Engine Computer "LIFETIME WARRANTY"

Either way, I do believe I have the ability to marry a PCM via Forscan and a USB OBDII adapter

Interestingly, the starting circuit doesn't involve the PCM. I'm looking at wiring diagrams and the ignition goes to the cluster, which controls the relays directly (besides for the clutch or range sensor switch interrupts). I guess that's not strange considering a traditional Starting circuit, but it did surprise me since PATS errors are so eager to disable the starter
 
SCT is going to try their hand at recovering it. Not a bad deal, all I have to do is ship the PCM, tuner, and cables to them. Besides the "immobilized car" part of the deal, of course. They'll test, attempt to recover, and ship back for free. Good customer service, but I wish I had known bricking the PCM was a known possibility

Word of advice for others that want to tune their car: park it in the least inconveniencing way, should it immobilize itself, preferably with tow truck access. Disconnect any extra electronics, turn off everything besides the ignition, and hook it up to a battery charger. Some people claim they park at the dealer to program it! If your LS is your only car, definitely be aware that bricked PCMs are not unheard of and you may need alternative transportation. I had to push mine down the driveway, pull my other car over the lawn, then push it back up the driveway. Hopefully I can skip the dealer tow with Forscan if SCT can't recover the current PCM
 
Interesting. I’ve had tunes with my SCT x3 that failed to upload and stopped mid way just to have it revert back to start. I think it froze once and I unplugged it and plugged back in and set it back to stock before attempting again.

A huge factor is battery charge on these tunes, always be sure the battery is good and fully charged before doing it.

I’m just really surprised you couldn’t get it back to stock since the first thing the tuner does is read the stock program before trying to upload a new one.

Good on them to help you out. Keep us posted
 
I went through the exact same thing with a "tune" from Torrie @ unleashed tuning.

I'm not trying to bash him but after spending an entire weekend emailing him back and forth trying to explain to him that the car will not run with the tune that he sent me, but will run with the generic tune that the sct has pre-programmed in it

Then it's not the same exact thing. My PCM has no communication at all and I can't load any tunes, be it custom, stock, or recovery. The car doesn't acknowledge that the PCM is present and my OBDII readers suddenly can't connect

No updates yet. I assume my PCM is currently sitting on a workbench in front of an angry SCT technician
 
SCT was unable to recover it on the bench, so they sent me a different PCM and new X4................. but they forgot to send me the tuner cables. I'll see those in two days and try the tune again then. It also would have been nice to have been updated on status and given any explanation rather than only finding out it was coming back because Fedex notified me

I thought the PCM had to be married to the cluster to keep PATS happy? I installed the pcm and it started up fine. The PCM did match the 4-character code on the label. I pulled over a dozen P/B/C codes through forscan, but I'm sure most/all are no longer active since there's no warning lights and no drivability issues. Just some leftovers from the pcm and battery being disconnected
 
SCT must have found a way to copy the security data from your PCM into the replacement. I guess that part of its memory was still intact and reachable? Interesting...
 
They did mention something in their notes about being able to recover it with an X3, but the phone tech didn't have any info beyond that
 
Update - tuned

I returned the X4, then found an X3 locally. I re-bought the tunes for the new device. I drove it 20 minutes beforehand to charge it and put it on a trickle charger (in a serviceable parking spot, this time). It still took 4 attempts. It failed the first 3 times somewhere in the downloading stock tune phase. All the while, the battery voltage was dropping slowly. These tuners are extremely sensitive to voltage change, not just voltage drop. I think what happened was that on the 4th attempt, where voltage went from 11.8x to 11.6x, was that the change was finally small enough to let everything go through. I guess that was the point where the trickle charger could keep up enough

Now I'm going to make a transmission thread...
 

Members online

Back
Top