venom09

Cobalt LNF
Car won't start?!
Do I need the EBCM for the car to run? I plan to race the car and don't care for ABS or TC...
We just picked up a used 08sstc coupe with and she was running fine during the test drive on the way home it started acting up - speedo and tach went to zero and power steering warning on the DIC! But the engine kept running till I got home and shut her off.
Now she won't turn over... Just click in the start position. Everything turns on, lights and fuel pump. Checked all the basics like ECU connectors ground wires etc nothing.
HPtuners show "unable to connect to vehicle".

Took it to the dealer and they want to replace the EBCM for $1000!? Shouldn't they look into the ECU? Does this make sense??

iboost

iTrader: (16)

It makes sense that they wanna charge you a grand, cause, well...its the dealer but people on this forum sell the ECM for like $100-150

venom09

ECU yes... But why the EBCM? That only control ABS and Traction no?

ECaulk

iTrader: (6)

For the ECU to start is has to communicate with the EBCM, some ECU functions are based off EBCM data

tomj77

iTrader: (2)

The bcm controls more then that

SSlobalt

It also stores your mileage, doesn't it?

ECaulk

iTrader: (6)

It does a lot, I dont think GM has released everything it does. I'm pretty sure its the little black box required on all cars now, not sure when it was passed as a law

tomj77

iTrader: (2)

just checked the wiring diagram, literally everything goes through the bcm I guess I can post those eh

venom09

Ok thank you for the replies... I had no idea and did some research...

I looked up my vin on the ACDelco website and 2 part numbers popped up... 1 for the module and 1 for the complete assy.
25826700 is the module that you can find on few websites for $150 - $250. But this part number also show that it fit the LT models and some G5 models!?
I thought the LNF would have a different module...

I also looked up the 09 SS and it has another part number and it does not fit any other cobalts or G5's?

tomj77

iTrader: (2)

What I posted the schematics for them yesterday, where did it go .

venom09

Please post them again or send me a PM.

tomj77

iTrader: (2)

ya I remember I previewed my post and forgot to actually post, ill do it right now

tomj77

iTrader: (2)

venom09

Thank you!

tomj77

iTrader: (2)

u are welcome. if u need any other schematics let me know. I got everything for the car.

venom09

Thank you.
Update: Turned out they meant the Electronic Brake Control Module... So I bought one off GMonline and a ZZP PCM just incase.
installed them last night and still a no start.
All the accessories turns in but the engine does not turn over... Same as before
To check the starter I jumped the starter signal feed manually and she turns over and starts immediately but, dies within seconds...
So it's not the battery, starter, PCM, EBCM... I checked all the basics again like loose grounds and blown fuses. Nothing.

Any ideas?

venom09

Can you help me with a schematic for the PCM?
I've traced my problem to a bad connection between the PCM and EBCM (electronic brake control module)

blueLNFftw

iTrader: (16)

Yea.
Is the security light staying on?

venom09

No, already took care of that. The dealer did all the recalls and programmed the new keys and such...

Yesterday we found this after a lot of checking and fiddling:
When you wiggle the small connector (from the PCM) loom and the loom going to the EBCM she will fire and run fine...

Tonight I am opening up the wiring loom and check wires.

venom09

It was a bad pin connector in the EBCM plug - one of the 2 wires that runs directly from the PCM to the EBCM.
She runs like a top now

350ss

iTrader: (1)

where do those type of schematics come from? much easier to read than the stuff on alldata

do you have one for the ecm? feel free to pm if you want

sorry for the hijack to the op