3rdgenfan

So, first off I have searched since this problem started up and have checked the grounds in the engine bay, taken the BCM apart and cleaned the surface of any water build up/residue plus baked it for about 10 min to evaporate any residue from the electronics cleaner, the issue still was a random occurrence so I figured I'd replace the Ignition Switch (since it was cheap on amazon) with zero change.

Heres what happens:
Currently when you go to start the car it will either do nothing but crank, or if it fires up it will sputter for a second or two and die. Sometimes you will be able to get it to rev for a few seconds and then dies out; when it manages to start you can smell the fuel that's going through the exhaust.

About a week ago I was able to fire it up without any hiccups, got about a 1/2mi from home when I went to turn, put my turn signal on and the car died. Luckily I had enough momentum to coast through the stop sign/intersection..about an hour or two later I was finally able to get it to start but it would miss/run like crap and the only way to keep it running was to leave the turn signal stalk in the upright (Right Indicator) position which about a minute or two later it cleared up and ran perfectly.

Get it home and started to check stuff out; with the car in the ON position (not running) using the turn signal they would flash once and the indicator light would go to a dim green and sit there and if you let it sit there for like 10 seconds it would start to rapidly flash the indicator lights. With the parking lights on, you can tell they are very faint and when trying to start the car the cluster lights will flash...and again it will sputter or just crank.

I'm at a loss currently, pulled some codes and forgot to mark which ones were "current" but they're all recent since I wasn't getting codes last weekend.

They are:
TCM:
C1255 BCM Malfunction?

BCM:
B0507 (Had the Left DRL relay out)
B2578 (This one has me curious)
B2587 (I have the CL Bypass, might be the cause of this code)

the usual RFA codes when the battery dies/disconnected.

Once I saw the RF Turn Signal circuit short to voltage I unplugged any relay/fuse in the interior box that had to do with the front lights and it still didn't start.

Any help, Corvette Forum? I just want to know where to attack next so I can get this thing ready for spring/summer.........and a blower.

3rdgenfan

Also, if it helps any:

I took off the accordion looking tube on the passenger side door, saw no issues with the female pins, no open wires...put it back together. Before that though, if I were to get in the car and just hit the brake pedal (key not even in ignition) the Odometer would show, and the chime would go start to go off randomly.

A quick update regarding the turn signals/gauge cluster lights flashing:
Parking lights on with turn signals: One flash and then goes solid but dim.
No Lights with Turn signals: That indicator (left/right) plus the cluster lights flashing rapidly

Bill Curlee

C1255 is BCM DEATH.. If you cant clear that DTC,, The BCM needs to be replaced..

DTC C1255 EBTCM Internal Malfunction

DTC C1255 EBTCM Internal Malfunction

Circuit Description
This DTC identifies a malfunction within the EBTCM.

Conditions for Setting the DTC
An internal EBTCM malfunction exists.

Action Taken When the DTC Sets
• A malfunction DTC is stored.
• The ABS/TCS/Stabilitrak® is disabled.
• The ABS indicator is turned ON.
• The TRACTION CONTROL indicator is turned ON.
• The DIC displays the SERVICE STABILITY SYS message.
• For some DTC C1255xx, the Magna Steer® is disabled and the DIC displays the SERVICE STEERING SYS message.

Conditions for Clearing the DTC
• The condition for DTC is no longer present and you used scan tool Clear DTCs function.
• The condition for DTC is no longer present and you used the On-Board Clear DTCs function.
• The EBTCM does not detect the DTC in 50 drive cycles.

Diagnostic Aids
• When the scan tool displays the DTC, 2 more numbers follow the DTC. Note the 2 numbers and any other DTCs. The 2 numbers with the DTC are an engineering aid in order to determine the cause of the internal malfunction.
• A DTC C1255e2 can be caused by a battery or module connector disconnect. Inspect for a recent battery disconnect or module connector disconnect before replacing the EBTCM.
• A DTC C1255m5 can be set along with any wheel speed sensor DTC. Diagnose any wheel speed sensor DTCs before replacing the EBTCM.
• Make sure the integrity of the connection between the EBTCM and the BPMV is secure, tight, and free from corrosion.
Step Action Value(s) Yes No
1 Did you perform the Diagnostic System Check? -- Go to Step 2
Go to Diagnostic System Check

2 Are any EBTCM DTCs present other than C1255xx? -- Go to Diagnostic Trouble Code (DTC) List
Go to Step 3

3 1. Turn OFF the ignition.
2. Disconnect the EBTCM harness connector.
3. Check for damaged, pushed out, or miswired terminals.
Was any damage found? -- Go to Step 4
Go to Step 5

4 Repair as necessary. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair? -- Go to Diagnostic System Check
--
5 Replace the EBTCM. Refer to Electronic Brake Control Module (EBCM) Replacement .
Did you complete the repair? -- Go to Diagnostic System Check
--
________________________________________

3rdgenfan

Bill,

After clearing the DTC's I haven't gotten the RIP BCM code, I ended up unplugging the harness that goes to the rear lights and my hand got soaked with water. I went and did the same things I did before, pressed brake pedal/checked hazards/turn signals and all was acting normal (for having a bulb "out") and all the issues went away...still won't start though. hah.

This is what is was doing before I even got underneath the car, hazards were just a test but you can see that it makes sense with once the rear lights getting power, other things would happen.


Only current code is for the Tail Lamp Circuit being open, and I get the Service Stabilitrak Sys with that harness unplugged.

3rdgenfan

All fixed, there was a ground strap on drivers side of the rear light/fuel harness that managed to back all the way off of the stud.

Cleaned up some other grounds, replaced the ignition switch and the fuel pump relay, so out of this whole project I'm out like 65 bucks. Not too shabby.