Replaced the EBCM, now car wont start
 

I just replaced the EBCM in my 2002 Z06, The car ran befor I started the swap. I swaped it out with a new GM unit. I then got in and cleared all the codes. When I tried to start the car I just get some clicks and the PCM and TCS both show the No Comm code?
what went wrong?

What did you do exactly(include all steps). Post your codes.

It's because they need to be sync up.

My boo boo thought it said "BCM" not EBCM" my bad.

I will get the codes again later, What I did is as follows
The car is on a lift
I disconnected the MAF and removed the air bridge of the vairam intake
I disconnecter the upper coolant hose
I unplugged the 2 wire harnesses to the EBCM
I then removed the 6 screws
I seperated the EBCM from the pump
I reinstalled the new GM EBCM
reinstalled the 6 screws
I reattatched the 2 wire harnesses
then the upper coolant hose
then the air bridge and MAF
I then cleared all the codes in the car
I tried to start the car and it turned over 1 time then click
The car now says PCM no comm, TCS no comm when I pull the codes
I then unbolted the grounds just above the EBCM and cleaned them and reattatched them, Still get the No Comm errors and just clicks whan the key is turned
I tried to check Batt volts and got 12.02, but my meter is not trustworthy.
I then tried to start it again and no luck , and now the dash says low voltage

Disconnect the EBCM just to rule it out-should not have anything directly to do with starting since the car can run without the module installed.

check your battery cables for security. Try a jump start, or put it on the charger.

:iagree: Give that a shot -

Plus are you sure GM got you the correct part number for you year Vette?

There are many, especially if yours has AH and the one you purchased does not and visa versa.

Do the numbers match up on the two? new one and old one?

Let us know the numbers if possible.

Thanks,Matt

The EBCM match exactly and are what the GM computer says goes with my VIN
I may try a battery swap

Battery:yesnod:

I agree,, disconnect the new EBTCM. ry cables are properly torqued in place. Make sure that the batte Then clear ALL the DTCs and try to start it. If it start doesn't start, read and post the DTCs. If you see NO COMS, open BOTH doors and shake the crap out of the accordion tubes and see if that changes things.


BC

Dropped in a new red top opti battery and cleaned up the batt cable connections and it started on the 1st crank
so one problem solved, but I still get No Comms to the ABS code
Do I need to go to the dealer and have them flash it with a tech II?

No specific codes....or just no comm? You need to check for 12 volts and ground to the connector. If good, swap in the old EBCM, and see if you get the same result.

:yesnod:

Dude check the fuses under the panel in the engine compartment!

I had one pop and it did the same thing - there will be a MAXI fuse and a smaller one so check "BOTH" - my smaller one is the one that popped! Replace it and perfect -

don't know why it did it nor has it done it again.

Thanks,Matt

EBTCM is a plug and play. No dealer requierd. I agree, FUSES, and the ground. Please read and post the codes with the IGNITION ON engine running. Clear ALL the DTCs and see if anything returns.

Just checked the underhood fuses, all were good. I am worried that it is a harness issue, and that could cost me big

codes with or without enging running?

Time to break out the meter and get some critical voltage readings.. You have to PROVE that you have the correct voltages / and ground paths. Just because the fuses are good, doesn't mean that voltage is there.

BC

How exactly did you go about determining, that the EBCM was bad in the first place?

I pulled the codes when i got the car and got
P1571
C1248
C1254
U1040
and a code for the outside air temp B0333
Brandon at ABSfixer said it was the EBCM that was fried and that he could not fix those codes
So I got a New EBCM from a dealer swaped it in and now get no comms