Chevrolet Colorado & GMC Canyon Forum banner
1 - 15 of 15 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter · #1 ·
What's up 355 nation? Hoping someone can help with an issue I'm having with my 09' 5.3L 4x4. Seems like truck is severely under powered, occasionally speedo needle jumps around as I accelerate, and every once in a while I get an engine light that shuts off after the truck sits overnight. While it was on I scanned it and got 3 codes:
*U0073 Control Comm. Bus A Off
*P069E Fuel pump Control Mod. requested MIL Illum
*P0700 Transmission Control Sysem (MIL Request).
ECU, Transmission control module, speed sensor, accelerator pedal, fuel pump control module all checked for proper operations or replaced with new. Not sure where to look next. Speedo needle jumping around has me confused. Thinking all these codes are related. Anyone ever experience a problem like this or similar?
 

·
Premium Member
Joined
·
1,125 Posts
The first place everyone goes is an issue with the grounds. Check your splice packs. I’d also check your battery. These trucks are fairly sensitive to voltage fluctuations imho.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #3 ·
The first place everyone goes is an issue with the grounds. Check your splice packs. I’d also check your battery. These trucks are fairly sensitive to voltage fluctuations imho.
Thanks WV Native...appreciate it!
Battery is fairly new and I have checked grounds. Found nothing obvious. I have not checked the actual wires themselves though. Possibly a broken wire somewhere?
That’s my next step...
 

·
Registered
Joined
·
521 Posts
The "splice pack" ground points in the engine compartment, on each fender are notorious for buggy behavior. Search for "G105" and "G106" on this site for details.
 

·
Registered
Joined
·
3 Posts
dude i would check the Fuel pump Control Mod when mine failed code keep coming up then finally the Fuel pump Control Mod failed i was left on side of express way mad aF so I would change that or check the connector on it.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #8 ·
dude i would check the Fuel pump Control Mod when mine failed code keep coming up then finally the Fuel pump Control Mod failed i was left on side of express way mad aF so I would change that or check the connector on it.
Thanks HummerKid! Fuel pump control module was one of the first things I replaced. I believe there was a recall on that part even though it didn’t pop up when I searched myself.
Question...I had seen in another post of guy having similar issues and linked it to what he called the PCM. Is that the same thing as the ECM or ECU? Never heard of a PCM....
 

·
Premium Member
Joined
·
547 Posts
PCM - Power Control Module. Pretty sure that has been present in Colorados since introduction. You probably have heard this module referred to something else in other vehicles.
 

·
Registered
Joined
·
84 Posts
Since I own the same, 09 v8 4x4, curious to know what you find.

I do have some questions, 1. Does the miss happen after warm up or apparent even with a cold start? How about above a certain speed or RPM?
Basic checks for any vacuum hoses off or weathered with cracks? Use a mild soapy water to check for leaks. Is MAF cleared of any debris? ECU/PCM clean and dry? There was an article related to water in the ECU/PCM tray or connector that had the same symptoms. Any connectors wet on the underside or near the windshield water tray?
Also, listen for any injector tick during the loss of power...

Let us know.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #11 ·
Since I own the same, 09 v8 4x4, curious to know what you find.

I do have some questions, 1. Does the miss happen after warm up or apparent even with a cold start? How about above a certain speed or RPM?
Basic checks for any vacuum hoses off or weathered with cracks? Use a mild soapy water to check for leaks. Is MAF cleared of any debris? ECU/PCM clean and dry? There was an article related to water in the ECU/PCM tray or connector that had the same symptoms. Any connectors wet on the underside or near the windshield water tray?
Also, listen for any injector tick during the loss of power...

Let us know.
Hey 09BlkV8,
Thanks for joining the conversation, let me answer your questions:
Ok... as the truck warms up the issue becomes more apparent for sure. When it starts acting up, tranny shifts really hard from 1st to 2nd gear, between 2500-3000 rpm. I couldn’t tell you what speed because the needle jumps up and down so badly but it’s not more than 25-30 mph. MAF seems clear and no water at all in or near the ECU or in the tray. Could not find a vacuum leak but I’m not sure I’m checking the correct points. Your last question caught my attention...definitely hear a tick from the injectors.
Your thoughts are much appreciated!...Ty
 

·
Premium Member
Joined
·
811 Posts
I would take care of the ground splice packs before doing anything else. A poor ground connection will cause electronics to do weird things. I know from experience, my truck did some weird things a few years ago. Here is a link to the thread I started: Electrical gremlin? I followed the advice given on the ground splice packs and in the last 5 years and 100,000 miles the problem has not come back. I have a 2010 V8 Z71 4X4. The splice pack repair is quick and easy and even if it does not happen to be the cause of your current problems (although in my mind it is a strong suspect) doing the repair now could head off future problems.
 
  • Like
Reactions: Kenzen

·
Registered
Joined
·
7 Posts
Discussion Starter · #13 ·
I would take care of the ground splice packs before doing anything else. A poor ground connection will cause electronics to do weird things. I know from experience, my truck did some weird things a few years ago. Here is a link to the thread I started: Electrical gremlin? I followed the advice given on the ground splice packs and in the last 5 years and 100,000 miles the problem has not come back. I have a 2010 V8 Z71 4X4. The splice pack repair is quick and easy and even if it does not happen to be the cause of your current problems (although in my mind it is a strong suspect) doing the repair now could head off future problems.
TY 10Canyon53 good advice...plan on tending to those splice packs this evening
 

·
Premium Member
Joined
·
811 Posts
TY 10Canyon53 good advice...plan on tending to those splice packs this evening
If I remember correctly it only took me about 15 min per splice pack. I didn't take them apart and redesign them, I just took them loose from the fender, cleaned them up with a wire brush, sanded the contact point on the fender to bare metal, re-bolted them in place and sprayed battery post protector over it.
 
1 - 15 of 15 Posts
Top