Pontiac G8 Forum banner

1 - 20 of 29 Posts

·
Registered
Joined
·
96 Posts
Discussion Starter #1
Hi Guys

This past weekend, I tried to use my G8 just to found out that when turned on, it shutdown itself down after a few minutes. When I checked DIC display, found the power reduced message in it. I the scanned it with my handheld device and found a Crack Sensor error p0335. I erase the code and tried to restart the car and the car was unable to start. So I understood that the battery was the problem. Took out the battery and indeed was bad, and bought a new AGM battery. After hooking it up, I tried to start up and the car was unable to start. By no starting I mean that all accessories are on (radio, Ac fan, lights) but once I turn the key, no action from starter can be heard. I rescanned the car, and now it shows a P0604 code. This error is the ECM memory access, so I read all the related post about it in the forum, recheck the battery, checked the fuses and relay related to the ECM and interchange them with others fuses relays to make sure without any success. Is possible that the ECM could have been corrupted by a bad battery? Any ideas would be appreciate it !!

Thanks!
 

·
Registered
Joined
·
1,999 Posts
Leave your battery disconnected over night, then try reconnecting again.
 

·
Premium Member
Joined
·
4,580 Posts
Highly unlikely the engine computer module was damaged by a bad battery. However, could see inadvertently reversing the battery cables causing a fair amount of damage. Stranger things have happened. How did you determine the battery was the issue? Curious, what brand of battery did you purchase?
 

·
Registered
Joined
·
96 Posts
Discussion Starter #5 (Edited)
Highly unlikely the engine computer module was damaged by a bad battery. However, could see inadvertently reversing the battery cables causing a fair amount of damage. Stranger things have happened. How did you determine the battery was the issue? Curious, what brand of battery did you purchase?
I always read that battery issues make the car do strange things and codes. So was my first item to check. I bought a Bosch AGM. To clarify, I didn't reverse the battery cables.
Thanks!!
 

·
Premium Member
Joined
·
4,580 Posts
Currently, am using a NAPA brand AGM and thus far it seems to be holding up quite well. Wanted to eliminate the possibility of acid leaking into the the trunk compartment from a regular battery and spent the extra cheddar for reassurance. Bosch alternators and starters seem to be spot on, but have yet to purchase one of their batteries. Here's a thread that might be worth a peek... https://www.g8board.com/threads/battery-ground-bolt-read-and-check-yours.224746/
 

·
Registered
Joined
·
96 Posts
Discussion Starter #7
Currently, am using a NAPA brand AGM and thus far it seems to be holding up quite well. Wanted to eliminate the possibility of acid leaking into the the trunk compartment from a regular battery and spent the extra cheddar for reassurance. Bosch alternators and starters seem to be spot on, but have yet to purchase one of their batteries. Here's a thread that might be worth a peek... https://www.g8board.com/threads/battery-ground-bolt-read-and-check-yours.224746/
Thanks I will check this also!!! and report back!
 

·
Registered
Joined
·
96 Posts
Discussion Starter #8
Reporting back, checked the negative ground bold in the truck, no sign of rust. Left the battery 48 hours disconnected.

Video
 

·
Registered
Joined
·
12 Posts
Your code is for an internal ram memory failure- you can damage an ecm by low voltage (amperage spikes) conditions. seen it happen especially when there is bad ground failures.....
That said. lets diag properly:
first erase the code, cycle the key to off, open door and wait 30 seconds. turn key to run (don't crank) and back to off. recheck if code re set. if it did:


The main fuses to concentrate on are:
rear fusebox= F10-(ecm batt)
underhood fusebox= F28 (ecm 1), F39 (eng ign)
All (minus ecm batt)of these circuits connect/pass thru via connector X102- which is right front of strut tower. make sure there is no corrosion in there. ECM-batt is has a connector on the inside right kickpanel.
The ground to the ECM is bolted to front of right cylinder head under evap solenoid.
Relays responsible for power to ecm are the PWR TRN (feeds fuse F28) & IGN relay (feeds fuse F39)
As a tech, we probe directly at ecm (we have special test probes that don't damage ecm connector). those circuits are on ecm connector X1; #19 (feed back from f28), #20 (feed from f10), #47(feed from f39).
Ground is #73.

  1. Test the voltage and ground inputs to the ECM for the following:
    • A short
    • An open
    • High resistance
    • If all circuits test normal, replace the ECM.
 

·
Registered
Joined
·
96 Posts
Discussion Starter #12
Your code is for an internal ram memory failure- you can damage an ecm by low voltage (amperage spikes) conditions. seen it happen especially when there is bad ground failures.....
That said. lets diag properly:
first erase the code, cycle the key to off, open door and wait 30 seconds. turn key to run (don't crank) and back to off. recheck if code re set. if it did:


The main fuses to concentrate on are:
rear fusebox= F10-(ecm batt)
underhood fusebox= F28 (ecm 1), F39 (eng ign)
All (minus ecm batt)of these circuits connect/pass thru via connector X102- which is right front of strut tower. make sure there is no corrosion in there. ECM-batt is has a connector on the inside right kickpanel.
The ground to the ECM is bolted to front of right cylinder head under evap solenoid.
Relays responsible for power to ecm are the PWR TRN (feeds fuse F28) & IGN relay (feeds fuse F39)
As a tech, we probe directly at ecm (we have special test probes that don't damage ecm connector). those circuits are on ecm connector X1; #19 (feed back from f28), #20 (feed from f10), #47(feed from f39).
Ground is #73.

  1. Test the voltage and ground inputs to the ECM for the following:
    • A short
    • An open
    • High resistance
    • If all circuits test normal, replace the ECM.
I will be doing the cycle and re-checking of all those fuses and relays. THANKS for the feedback!!!
 

·
Premium Member
Joined
·
1,229 Posts
Thanks for the input!! I will check on that also!
If you determine that the BCM is bad, you can purchase a new one online along with purchasing a VXDIAG VCX NANO and reprogram it yourself.

It'll be cheaper than visiting the dealer and you'll then have a Tech II on hand.

I replaced my BCM and reprogrammed it the same way when the brake lights stayed on permanently in my vehicle (internal BCM short).
 

·
Registered
Joined
·
96 Posts
Discussion Starter #14
If you determine that the BCM is bad, you can purchase a new one online along with purchasing a VXDIAG VCX NANO and reprogram it yourself.

It'll be cheaper than visiting the dealer and you'll then have a Tech II on hand.

I replaced my BCM and reprogrammed it the same way when the brake lights stayed on permanently in my vehicle (internal BCM short).
Thanks!!!! Good information, Thanks for sharing!!!
 

·
Premium Member
Joined
·
4,623 Posts
If you determine that the BCM is bad, you can purchase a new one online along with purchasing a VXDIAG VCX NANO and reprogram it yourself.

It'll be cheaper than visiting the dealer and you'll then have a Tech II on hand.

I replaced my BCM and reprogrammed it the same way when the brake lights stayed on permanently in my vehicle (internal BCM short).
Is there a version that works on a 64 bit system?
 

·
Premium Member
Joined
·
1,229 Posts
Is there a version that works on a 64 bit system?
This works on a 64-bit system despite what the listing says. It is working perfectly on my 64-bit AMD A8 laptop with Windows 10.

If you want, we can create a thread with the ins and outs of getting it setup to work correctly.

What I'd like to get is a cheap touch screen Windows 10 tablet for portability like Mitch O. did in the review for the Wi-Fi version.

$119.95 + 5% coupon: https://www.amazon.com/dp/B074365Q6H/

$120 for Wi-Fi version: https://www.amazon.com/dp/B06XDHF3XX/
 

·
Registered
Joined
·
266 Posts
This works on a 64-bit system despite what the listing says. It is working perfectly on my 64-bit AMD A8 laptop with Windows 10.

If you want, we can create a thread with the ins and outs of getting it setup to work correctly.

What I'd like to get is a cheap touch screen Windows 10 tablet for portability like Mitch O. did in the review for the Wi-Fi version.

$119.95 + 5% coupon: https://www.amazon.com/dp/B074365Q6H/

$120 for Wi-Fi version: https://www.amazon.com/dp/B06XDHF3XX/
GXP25 if you wouldn't mind doing this, I would really appreciate it. This device can do everything a tech II can or at least all the important functions we need? This is the first time I'm hearing about it. Only ever heard of the "China knockoff" Tech II.
 

·
Premium Member
Joined
·
1,229 Posts
GXP25 if you wouldn't mind doing this, I would really appreciate it. This device can do everything a tech II can or at least all the important functions we need? This is the first time I'm hearing about it. Only ever heard of the "China knockoff" Tech II.
This does everything the Tech 2 can do with Tech2win. It even simulates the CANdi module that is needed for our CAN bus vehicles. I've downloaded all of the various PCMCIA cards/modules for the various GM vehicles.

I've used it to display the real-time misfires graphic.
 

·
Premium Member
Joined
·
1,229 Posts
Here's a single frame of a video I took of Tech2win (running on a 64-bit Windows 10 laptop) in the real-time misfire graphic of my vehicle.

IMG_9641.jpg
 

·
Registered
Joined
·
96 Posts
Discussion Starter #20 (Edited)
Update, Trying to diagnose my car because its far away from where I live, so that's why it’s taking so long to report back. I'm not an expert but leaning a lot in the process of electric diagnosing. I have been checking with the process that GOODWRENCHDAVE and GXP25 advised me and also the 5v reference circuits. In the process of checking the car started doing this sound on the starter side and as you can see, the engine light in the instrument panel is like flashing with the sound. To me its like a lose ground, but I'm no expert


I haven't finished yet, but any ideas on this new development maybe will help!!!

Thanks
 
1 - 20 of 29 Posts
Top