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Tries to start then stalls and dies

jbennett

Full Member
Joined
Dec 24, 2019
Messages
12
I started having problems a few weeks back where the battery would seemingly be dead after sitting a few days. I had the battery checked, after charging it multiple times, and it was indeed bad. I got a new battery and things were great for a few days, then the problem was back. A new problem came up where it would try to start and then die. I could jump it and it would be fine so I figured it was the battery but nothing makes sense as this is brand new. Once it was charged I get the codes. see below:

Current Faults
P0740 - Torque Converter Clutch Circuit
P0758 - Shift Solenoid "B" Electrical
P2761 - Torque Converter Clutch Pressure Control Solenoid Control Circuit/Open

Pending Faults
P0753 - Shift Solenoid "A" Electrical
P0785 - Shift/Timing Solenoid

I took it to a local Firestone to get a diagnostics ran on it. They called and told me it wouldn't start, like I had problems with earlier where it would start then die, and it needed a new ignition switch. I let them replace it. Once they got it in the shop, they called and said I needed a new transmission. I brought it home after calling another mechanic shop for a second oppinion. The second mechanic said he was an AV as well and it is some electrical problem to the transmission I needed to trace out.

I brought the truck home and was able to drive it for a few days until today. It is back to not starting and I have no idea what to do from here. When I put the key in the ignition I do not get a door ding like I usually do. I also have the check engine light, abs light and battery light displayed. The battery gauge shows about 10 volts instead of 12. I checked some fuses with one of those test lights and I do not get lights on the PCM B (which is new) or the TBC IGN1 fuses.

I am at a complete lost and could really use some guidance.
 
What year do you have
 
I suspect a bad alternator.

If I am reading it correctly, when the new battery was fresh, you were able to start and run the engine just fine.

Everything was fine right after a full charge, for a while.

Later the new battery showed lower than normal voltage.

Your engine will run fine off of a fully charged battery, for a while.

Once the battery's voltage drops to a certain level, the engine dies and/or fails to start.

Pull the alternator and take it in to a parts store for testing.

Be prepared to buy a new alternator if it doesn't test out really good.
 
What year do you have

newavguy its a 2004.

I suspect a bad alternator.

If I am reading it correctly, when the new battery was fresh, you were able to start and run the engine just fine.

Everything was fine right after a full charge, for a while.

Later the new battery showed lower than normal voltage.

Your engine will run fine off of a fully charged battery, for a while.

Once the battery's voltage drops to a certain level, the engine dies and/or fails to start.

Pull the alternator and take it in to a parts store for testing.

Be prepared to buy a new alternator if it doesn't test out really good.

I tested the battery again last night with a multimeter, and it shows just over 12 volts. If the alternator is bad, would the below snapshot list also be a sympton? Additionally, the ODB2 port has no power so I cannot pull the latest codes.

Most recent snapshot:

Radio head unit powers on but no sound
No ding when the key is in the ignition
No ODB2 port power
Battery shows about 10 volts on the gauge
No power to windows/locks/mirrors but the driver's seat does adjust.

Thank you, EXT4ME, for the assist!
 
Fuses are blown for the cigerette lighter thingys is why OBD port is dead.

I wonder if you have mice chewing on wires, bad grounds etc....
 
Fuses are blown for the cigerette lighter thingys is why OBD port is dead.

I wonder if you have mice chewing on wires, bad grounds etc....

I thought I checked the cig fuse but I'll check again and report back.
 
Well maybe it is another fuse I forget which one but pretty sure under hood...
 
I had my alternator checked and it was bad. Now that its replaced, the truck will start. The issues which remain are below:

- No power to ODB2 port (both front aux power ports work and fuse is not bad)
- The driver's side windows, seat memory, and locks do not work (the mirror on the drivers side does work but not the passenger)
- Power windows work in the back two doors, however.
- Check engine light is on
- ABS light is on
- Battery light is on and the gauge reads about 10 volts but at the battery with a multimeter it reads ~12.5

I have run through the fuses under the hood and in the cab and all appear to be in working order. Could this still be a problem with my ignition switch which Firestone says they replaced?

Is there a way for me to test the window motors or the switch for integrity?

I am out of ideas and have no idea where to go from here.
 
It's the Passlock system going bad. All the same symptoms that I had. Changed the battery, installed a alternator and checked all the fuses and it still happened. Once I cut one wire everything worked as it should again and I've never had the problem return. You will have the passlock light on your dash once you cut the wire but I pulled the gauge cluster and covered the LED with electrical tape so I won't have to look at it ever again.

Soooo, I cut the YELLOW wire on BCM C3 Pin A6. C3 is the brown connector on the BCM Module underneath the steering column, which is really behind the knee panel. It will be connected to this:

BCM.jpg
2003-2006 Chevrolet Suburban1.gif
I even tried the NEWRockies bypass module which didn't work on my AV, but I noticed once I cut that yellow the truck fired right up.
 
Last edited:
It's the Passlock system going bad. All the same symptoms that I had. Changed the battery, installed a alternator and checked all the fuses and it still happened. Once I cut one wire everything worked as it should again and I've never had the problem return. You will have the passlock light on your dash once you cut the wire but I pulled the gauge cluster and covered the LED with electrical tape so I won't have to look at it ever again.

Soooo, I cut the YELLOW wire on BCM C3 Pin A6. C3 is the brown connector on the BCM Module underneath the steering column, which is really behind the knee panel. It will be connected to this:

View attachment 227373
View attachment 227374
I even tried the NEWRockies bypass module which didn't work on my AV, but I noticed once I cut that yellow the truck fired right up.

Mine starts up fine now but I have the power issues mentioned above. Do you think this could still be the passlock system?
 
It has been a while but I wanted to post the final resolution for my issues. A more reputable repair shop took a look at it and discovered the ultimate issue was the IGN 0 fuse slot. It has a loose wire and therefore does not provide proper power to the transmission. In the end, I never needed an ignition switch or a new transmission.

If it sounds like a fuse, it's probably a fuse.
 
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