E38 Standalone problems

[GAMEOVER]

(This is my 12th E38 Harness I have built with No Problems on the previous 11)...

I built a E38 standalone harness for a 2007 5.3ltr engine(58X GEN4) using a TH350 transmission...Brand new wires & connector's. I plug everything in, hook up power-ground-ignition & as soon as key is switched on can I hear fuel pump prime for 2 seconds & I can hear throttle body receiving power because it opens & closes quickly.... Injectors, coils & maf sensor all have power. I press on electronic pedal and nothing happens, I check power again & everything is fine!!! I took apart both connectors at computer & check all pins & locations & checked continuity for every wire & pin 10 times and everything checks out perfectly...So I plug in V2 into OBD2 port & with ignition ON I get "ERROR-VEHICLE NOT DETECTED" ...Checked pin location & continuity for High Speed GMLAN data bus (+ -) PIN's 27-28 both check out OK! Checked ground on PIN 73 and also checked power at computer on PIN'S 19-20-47 all 3 pins have power with ignition ON.. I check-recheck-check again-check again-recheck again & nothing!!! Next I pug ECM into Bench Harness & V2 connects just like normal & I notice I have 8 DTC's and they all have to do with Throttle Body & Electric Pedal, so I check connector's at TB & Pedal no damage & pins at connector aren't bent or anything. Verify that both pin location at connector match location on ECM connector & perfect-checked continuity too & checks out fine.....
I tried clearing DTC's on bench and they will not clear, I've tried it 5 times with no luck. Why will the Throttle body & Electric pedal DTC's not clear? Maybe this is my problem...but no matter what I do DTC's will not clear on this E38 ECM...

[GAMEOVER]

Anyone got any suggestions??? I'm pretty much stuck...

[Taz]

Hello GameOver,

I always learn something from your posts. As you know from my previous posts, I’m still getting up to speed on the Gen IVs, and what I don’t know greatly exceeds what I do know.

The only thing that immediately comes to mind may not be applicable to your current situation. As I understand potential Gen IV Throttle Body (TB) issues - the “base tune” in the ECM must be similar to the tune flashed in.

That is, beginning with an ECM from a Corvette, and flashing in a truck tune with the same OS, may cause TB issues - the reverse is also true.

If you are working with an original truck ECM and OS this phenomenon should not apply.


Regards,
Taz

[GAMEOVER]

Hey Taz,
The OS, ECM, TB & Pedal are all from the same Vehicle. But what gets me is that I can't clear the Pedal & TB DTC's...I think when I initially turned ignition on...The pedal & TB were not connected, so I connected them quickly without turning ignition off...

[GAMEOVER]

How do I clear trouble the codes...V2 will not clear...I don't know whats going on...:(

[GMPX]

Why will the Throttle body & Electric pedal DTC's not clear? Maybe this is my problem...but no matter what I do DTC's will not clear on this E38 ECM...

I'm not trying to sound like a smart a***, but the reason they won't clear is there is obviously a fault of some sort. It's like unplugging the coolant temp sensor and then questioning why the coolant temp sensor DTC won't clear.
It's quite common that ECM's will set a bunch of DTC's on a bench programming harness, it's when you put it back in the vehicle and then clear codes you need to follow what those remaining codes are telling you.

[GAMEOVER]

I was actually trying to clear DTC's on bench, because I couldn't communicate with vehicle. I found the problem though...my bad
I was one pin off on ECM connector X1 pin#32 I kept pinning out pin#33
32=APP Sensor 2 Signal.......33=5 Volt Reference