2014 Caprice PPV Swap - No Throttle

Using the all the vehicles components, L77 (6.0L) and 6L80. Also have the BCM and gas pedal from the vehicle....

Car starts and idles but no throttle response. When scanning, the pedal at idle is approximately 20% and goes to 80% when floored. The throttle position never moves when the pedal is pressed (stays around 20%-25%).

I have tested all the wires at the pedal and getting appropriate readings
Low Signal = 2-3 ohms to chassis ground
5V reference = 4.98 volts
APP1= .977-4.09 (rest to full throttle)
APP2 = .47 - 1.95 volts (rest to full throttle)

Test the low signal and 5V reference at throttle body and test correctly.

Getting the following codes:
P2120
P2122
P2127
P2128
* all in reference to APP

Have tried clearing codes and the P2120 is permanent

I'm thinking something shorted in ECM.

Thoughts??

post file

Attachment 93078

Here is the scan file.....

File showing accelerator position percentage increasing but throttle position not increasing Attachment 93174

I have checked all wires for continuity and tested what I can with DMM.

Am I missing something in programming?

Bought another ECM from the same as original vehicle (2014 Caprice), because all testing procedures related to the codes and accelerator pedal said replace ECM if circuits are tested correctly.

Took off the throttle body and keyed ignition on, butterfly/plate moves slightly and goes back to position at rest.

Starts and runs, no throttle still.

WIth second ECM getting following codes:
P2122
P2127
P2128
P2138
*Slightly different codes than previous ECM, but all still related to pedal. Never had the P2138 with first ECM

Here is the current tuneAttachment 93175

I would jump in here but my info stops at 2009, I would just be guessing if I offered any specifics...

So run through the charts for those codes. It has to be something obvious and detectable given what they are. What source are you using to verify wiring & pinouts?

using alldatadiy for wiring and pin outs

Cleared all codes and started the vehicle again today and let it idle for some time and never touched the accelerator pedal, only pedal code was P2122 (permanent).

While it was running tested wires at pedal, between the low reference and 5V wires had 5.01 volts for both APP1 and APP2. Tested each signal wire from pedal, APP1 tested at .970 volts and APP2 was .487 volts.

Also got:
PO315 Crankshaft position system variation not learned
UO101 lost communication with TCM
PO480 Fan 1 control circuit (haven't hooked up the fan wring yet)

Would you not get throttle if the ECM is not communicating with transmission (TCM)?

did any of this get resolved?

i bet the 101,102,103 DTC are not set correctly. ive been caught

had a similar issue with a conversion, was missing a 12v to the ecu.

Took a hiatus on the project for the winter.....

Got most things figured out, ended up the TCM was no longer communicating and I'm assuming the throttle didn't work due to "limp mode" induced because the transmission was not recognized. I think I bricked the TCM because I tried to write before turning the ignition on for 10 seconds (I have read this can happen). I got another TCM and was trying to just plug it into the harness without installing it to see if it would work, I could get no communication with HP Tuners at all. I was frustrated and just ended up bolting the TCM to the valve body and installing the valve body and installing the pan (basically buttoned the transmission up with the newer TCM). Once I did this there was again communication with HP Tuners. I was able to "write entire" and put my TCM software onto the newer TCM. Vehicle now starts, runs and has throttle control (with the factory pedal)...

Now my question is what other pedal options is there for this set up?? The factory Caprice pedal will not fit in the vehicle.

I have a C6 pedal and have tried to wire it according to diagrams I have found online and it does not function.

Any input would be appreciated!

Took a hiatus on the project for the winter.....

Got most things figured out, ended up the TCM was no longer communicating and I'm assuming the throttle didn't work due to "limp mode" induced because the transmission was not recognized. I think I bricked the TCM because I tried to write before turning the ignition on for 10 seconds (I have read this can happen). I got another TCM and was trying to just plug it into the harness without installing it to see if it would work, I could get no communication with HP Tuners at all. I was frustrated and just ended up bolting the TCM to the valve body and installing the valve body and installing the pan (basically buttoned the transmission up with the newer TCM). Once I did this there was again communication with HP Tuners. I was able to "write entire" and put my TCM software onto the newer TCM. Vehicle now starts, runs and has throttle control (with the factory pedal)...

Now my question is what other pedal options is there for this set up?? The factory Caprice pedal will not fit in the vehicle.

I have a C6 pedal and have tried to wire it according to diagrams I have found online and it does not function.

Any input would be appreciated!

As per schematics of both
Caprice APP pins listed as 123456. C6 pins listed as ABCDEF
APP pin position - 1=C, 2=B, 3=A...... 4=D, 5=E,6=F- for circuit # to be matching.

My Info from actual shop manuals- not internet! 2014 caprice PPV ... 2012 corvette vin Y

You saying the corvette pedal fits?

quick clarification- don't remember if the pin numbers are on the harness so clarification - when starring at the harness side connector tab upwards the pins are 654321 (1 is farthest right) same with c6Attachment 97793

Did some testing of each pedal assembly today.

The connector on the Caprice pedal looks more like the Standard Motor Products S2398 (also ACDelco 13577043). Sorry i don't know how to add pictures.

With the low reference and 5 volt wires hooked up to the harness I tested the APP wires coming from the pedal.

Caprice pedal on the APP wires:
.4V at rest to 2V depressed
.9V at rest to 4V depressed

C6 Pedal APP wires:
.4V at rest to 2V depressed
4V at rest to .8V depressed

It appears the C6 pedal is sending different voltages on one of the APP wires... so this C6 pedal will not work?

Can anyone confirm this is correct?

Thanks in advance for your time and assistance.

I was always under the assumption that most gen 4 pedals where interchangeable- but respective circuits needed to remain the same.
Did you recheck your wiring as per what i listed? two-A&C changed position!
What your asking is NOT how a part is tested as per the manual.Nor Info available in shop manual. Only someone with a scanner plugged into a vette could confirm that.
if your circuits are properly wired then your pedal is either no good or incompatible.
forget what the plug looks like- GM used square and oval plugs.... but it is the pinout that is important- respect the circuits!

Attachment 97798Attachment 97799

Goodwrenchdave,

Thanks for the information!

I tried to wire the way you said above:
1=C, 2=B, 3=A...... 4=D, 5=E,6=F-

It did not work.

Now when I wire the Caprice pedal in it does not work either, it was yesterday...... Guess i beeter try to scan for codes, maybe i trew a code or shorted something??

What do you mean by this?: Did you recheck your wiring as per what i listed? two-A&C changed position!

Quote:

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Originally Posted by wiringnatzi

What do you mean by this?: Did you recheck your wiring as per what i listed? two-A&C changed position!

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The two pedals do not have the same pinout positions. First and third terminal from right looking at connector from front harness notch up are reversed (A or position 1 is furthest right) look at picture. here is the TAC schematic for both cars
Attachment 97800
Attachment 97801

Goodwrenchdave,

Your help is much appreciated... been looking at schematics and wires for days.

Here is how each pedal connector is wired
Caprice (factory harness):
1 = 5V Ref (2); BN/RD
2= Signal (2); GN/WH
3= Low Ref; BK/VT
4= Low Ref; BK/BU
5= Signal (1); YE/WH
6= 5V Ref (1); WH/RD

C6
A= Low Ref BK/VT
B= Signal (2); GN/WH
C= 5V Ref; BN/RD
D= Low Ref; BK/BU
E= Signal (1); YE/WH
F= 5V Ref; WH/RD

Wish I knew how to upload pictures.. I could show both connectors.

Last night I wired the factory Caprice pedal back in after disconnecting the battery for awhile, it functioned.

Did not try to wire the C6 pedal in again..... a little hesitant.

goodwrenchdave,

Looking at the schematics (I have the alldata schematic for the caprice, its the same as your GM one), one question.

Does the 5V-1 and 5V-2 need to follow the signal-1 and signal-2?

On the corvette schematic they are on the same circuits, signal-1 with 5V-1 and signal-2 with 5V-2 vs. the caprice schematic the signal-1 is with the 5V-2 and signal-2 with the 5V-1....

goodwrenchdave,

Again thank you for the information.


Kept the pedal wired as above and wired it into the vehicle tonight and the C6 pedal is working!

Onto next challenges with the swap....

I did the same thing. turns out the 14 PPV is interchangeable with the C6. I went through much of the same issues you did. the pins needed to ebe figured out, but now am getting APP1 and APP2 within 1% of each other throughout the whole range. I hope this is resolved for you. If not, post up again and i'll work through which wires i connected to which pins on the x1 and x2 connectors.

~Ryan
Charleston, SC

Thanks Ryan,

Go that part of it figured out with the help of goodwrenchdave!

Onto next things, trying to get TUTD functioning?!

Quote:

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Originally Posted by wiringnatzi

Thanks Ryan,

Go that part of it figured out with the help of goodwrenchdave!

Onto next things, trying to get TUTD functioning?!

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how did the TUTD work out for you? PPV shifter?

~Ryan
Charleston, SC

Went through the same thing did all of what you have done and a heap more to find out it was the oil pressure switch giving the 5v ref a feed back and then shutting down the tpps circuit. (new pedal, ECM,Wiring check, Jumped 5v ref , made 5v ref out of three AA batteries and more LOL)
A common sign of this is not oil pressure on gauge.
Also had to unplug the MAP and replug in a few times.
LS2 with Higgins LS3 Heads, Magnuson , VCM16 cam, plus a few other goodies