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P0420 TWC System Low Efficiency Bank 1
P0430 TWC System Low Efficiency Bank 2
02 sensors
C1255 EBTCM Internal Malfunction
CEBCM Internal Malfunction
U1096 Loss of Communication with IPC
U1064 Loss of Communication with BCM
These are the codes I pulled from my car, would a refurbished pcm get rid of these codes after a tune or is there more that needs to be done? I'm really tired of my dash looking like a Christmas tree.
Thanks in advance.
As far as the P0420/0430 your CATS may be "smoked" OR you may have an exhaust leak anywhere from aft of the forward O2 sensor to forward of the rear O2 sensor on both sides...without a scan tool and doing some pin point testing (oxygen storage test) it can be difficult to diagnose 100%. The C1255 is the EBCM "death code"...if you can get a Tech 2 or a bi-directional scan tool you can do the "Automated Test"...if it doesn't pass the EBCM is toast. The other 2 U codes may just be power or ground issues with them !!...have you had the car long ??...I see this is your first post....WELCOME to the club !!
I know those were the o2 sensors I just forgot to delete those when I pasted them all. In the process of getting long tube headers so I'll fix those 02 sensors when that time comes. Also I don't have cats. I figured it was the death code but never hurts to double check. Ive had the car about a year or so though.
Thanks and please post all pertinent info when having issues...this helps us help you...including it in your profile helps !!...like I said unless you can find someone with a Tech 2 or similar to do the Automated Test” maybe wait until you can confirm that !!...also with the scan tool you can see if you can communicate with the IPC and BCM...if not check powers and grounds...also next to the BCM are 2 Star Connectors...remove the “comb” (bus bar) from the connector with the 9 wires...take some emery cloth and clean the comb...a few months ago a member had some issues with his data bus and we were trying to figure out why we could not communicate with some modules...even though the comb looked clean visually when the comb was cleaned we were able to communicate with those modules !!
Took what out ??...clear the codes and see if the U codes come back....best thing is to have a scan tool and see if you can communicate with those 2 modules....clean the comb...you can clean the other one too and then if you still have the codes you can check the modules power and grounds !!...I don’t think you told us what year C5 you have and mods ??
It’s BCM (Body Control Module) and not the PCM !!...BCM is at the passengers side footwell. This is the wiring from my ‘01...yours should probably be the same....as you can see the BCM and IPC are fed from the BCM1 and IPC fuse 25...if you have a voltmeter you can do a “voltage drop” check across the ignition switch...with the engine running take your voltmeter red lead and connect to battery positive...connect the black lead to one of the test points on top of that fuse 25....read the voltage
drop...you shouldn’t see more than .1 to .2 volts of a drop...try that and also the drop across fuse 23 (BCM 2).
I should of made an account a while ago. I really appreciate the help. I'll give you a follow up tomorrow. If it's a fix I'll owe you a couple beers. ��
I’ll see if I can find you the power and grounds for the 2 modules...clear the codes and see if the no comms come back...sometimes the car has a hiccup and will throw codes...if you clear them and they come back now you have an issue !!
Check and see if you see any corrosion inside...being inside the car it’s not as bad if it were outside the car. I have a terminal cleaning kit that has super thin files that you can clean those terminals with...I use a small wire brush on the combs...sandpaper will work too...just get it super clean !!...you just have to pop the plastic piece back onto the comb !!
Its all good now, and just in time for the weekend. I really appreciate it c5 diag. Definitely going to have to check your you tube out and follow it. Made my week to get my dash not to look like a Christmas tree and having to press reset 5 times to clear it every time I get in the car. Off to long tube headers and a tune.
SUPER SUPER !!...So did you find any corrosion either on the comb or in the splice pack ??...THANKS for subscribing...I’m in the process of doing a video on that serial data bus...hopefully can get it done soon !!...if anything pops up give us a shout !!...OH, a Corona with a twist of lime...LOL !!
Well it went off for a little but it's back on now. At least I found the problem, Tuesday I can take a good look at it. The teeth looked pretty clean, definitely no corrosion though.
Traction control codes
