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2010 Chevrolet impala LT flex fuel 3.5l v6

1107 Views 25 Replies 5 Participants Last post by  Impoor
I have a 2010 Chevrolet impala lt flex fuel 3.5 v6. I have been without a car since October. First my car started going into limp mode, it would stay running but when I hit the gas nothing happened. I took it to 2 parts houses and they both told me something different. I borrowed a obd2 scanner and every time it would give me a code and I would change said part, another code would come up days later and it still drove the same (limp mode) or rpms higher than normal. Since October, I have changed Map sensor, MAF sensor, camshaft sensor, wiring harness for the camshaft sensor, oil pressure sensor, VVT solenoid, changed the oil and filter, ect. It has always cranked and ran fine until recently and it wouldn't start, even though it has good power. Now its giving me a code (U0100) Lost communication with ecm/pcm "A" ..
I'm not sure what the A is but I did have a code that came back camshaft position sensor open circuit "A" which I changed the sensor and harness. I dont know if I need a Ecm/pcm or a TCU since they both run hand in hand. I truly appreciate any advice or recommendations you can give me. I have done all the work myself with the help of a obd2 scanner and Google. I'm out of options here. Does anyone have a wiring diagram for circuit "A" please.
1 - 9 of 26 Posts
Make sure your battery is fully charged and connections are good...U0100 not enough juice
Wiring issue ...short
Canbus A
At your DLC on pins 6 and 14 you should have a reading of 60 ohms for normal
If you get 120 ohms you have an open in the wiring
If you get 0 you have a short in the wiring
Did you by chance unplug the EBCM (abs brake module) of you did make sure the connector is seated properly...They can be tough to get right...lf it's not connected right it will cause some weird electrical problems...head scratchers lol
Oh yea DLC pins
Looking at connector top row three pins in from right is pin 6 and pin 14 is just below pin 6
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Just a regular multimeter.
Your library or auto zone web site has wiring diagrams
I use quilting needles and work well as back probes
Read this and start the tests as stated in this article
Your numbers are strange
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You have a short on the Can high side.. Get a wiring diagram for Can bus high side
Check all fuses ....turn key to on not start and check all fuses under hood and inside car fuse box.
I had a wiring diagram for your car but it magically disappeared when l tired to upload... Send it back google lol
You could go old school with a clamp type meter
At the computer seperate all the wires and turn the key on not start and measure the amps of every wire by one..The one wire with the highest amps is the circuit that has the short... Takes time but no fancy equipment needed.. Then trace that circuit for the short... 10 miles of spaghetti lol
"threw this code about 2 weeks ago."
It ran fine untill about 2 weeks ago when you got the U0100 code?
1 - 9 of 26 Posts