No communication

Tiny
KRISTAGIAMBELLUCA
  • MEMBER
  • 2008 PONTIAC G6
  • 0.6L
  • 4 CYL
  • FWD
  • AUTOMATIC
  • 99,000 MILES
Hi, I took my car to get inspected on Friday and when he hooked up to OBD2 plug the computer said, "voltage detected but no connection to vehicle." A few have said it is the lighter fuse but they work because I have been charging my phone just fine. Could it be the ECM fuse? Could it be the OBD2 plug needs to be replaced? Please help! My inspection is now two days over due. Ugh
Monday, October 2nd, 2017 AT 8:20 AM

20 Replies

Tiny
JDL
  • MECHANIC
  • 16,098 POSTS
Note the image. You said voltage was detected. In the picture, pin 16 is voltage, hot all the time, you can use a test light to check for voltage. Pins 4 and 5 are grounds, check for ground.
The other thing I know to check for is serial data. A digital logic probe should react to serial data and is safe. The logic probe will make all kinds of weird sounds to let you know there is activity, You will not know what it means, just that there is activity.
Did they try a different tester? If the vehicle starts and runs okay and the accessories work, it sounds like the PCM and BCM are okay? I guess I cannot rule out the obd 2 connector, itself, at the moment?
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Monday, October 2nd, 2017 AT 10:14 AM
Tiny
KRISTAGIAMBELLUCA
  • MEMBER
  • 4 POSTS
Thank you for that, it is a little confusing for me, but I am going to have a friend look at it. But yes, all accessories are working. I did notice last night and this morning that while my seat belt was on it was still telling me to put it on, (dining and blinking). Yes the car runs good, starts as well. No grounds were checked though so maybe that is it? And yes, two different testers at two different places.
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Tuesday, October 3rd, 2017 AT 6:05 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 51,574 POSTS
There is a fuse for the HVAC control that can be out not giving power to the ALDL connector.

Here are two guides and some diagrams (below) to help you run some simple tests. Fuse #13 and #16

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Please let us know what happens.

Cheers, Ken
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Tuesday, October 3rd, 2017 AT 2:37 PM
Tiny
KRISTAGIAMBELLUCA
  • MEMBER
  • 4 POSTS
Thank you Ken! I'll have my friend look at those tomorrow, he'll know more about it than I will. I'll comment on what the problem was and if it turned out to be anything anyone suggested. Thanks again!
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Tuesday, October 3rd, 2017 AT 3:18 PM
Tiny
DCCOLLINS1
  • MEMBER
  • 1 POST
  • 2008 PONTIAC G6
  • 2.4L
  • 4 CYL
  • 2WD
  • AUTOMATIC
Hooked it up to a OBDII and UO-100 loss of communications to ECM/PCMA. What is the problkem and how can I fix it?
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-1
Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
RACEFAN966
  • MECHANIC
  • 5,029 POSTS
In the under hood fuse box there should be a fuse labeled hvac cont or batt it is 10 amp if that is blown the scan tool won't communicate with the computer.
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
ZELLERDEREK4
  • MEMBER
  • 63 POSTS
  • 2009 PONTIAC G6
  • 2.4L
  • 4 CYL
  • FWD
  • AUTOMATIC
  • 71,040 MILES
I am not sure if these codes are stored in history or if its a persistant code but I found u2105 and u 2107 I believe these code were also being thrown around the same time my eps would cut out on me would these codes be thrown from a bad tpms? Hard the car up in the air yesterday and didnt see any thing wrong with abs modules but it also points to abs unless abs is part of the body module like the power steering, power steering cut out on me after I started it for the 3rd time this morning after car was warm and everything like that about 1 hour later I scanned the car and it came back with no code and 8 hours after that it had these codes again
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
My question is what are the exacr eps codes do you have?
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
WRENCHTECH
  • MECHANIC
  • 20,761 POSTS
These are going to be difficult codes to resolve.
The U2105 means the PCM lost communication
The U2107 means the BCM lost communication.

Having one of them can mean the module itself has a problem but having 2 different modules coding could mean a wiring issue.
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
ZELLERDEREK4
  • MEMBER
  • 63 POSTS
Im hoping to get exact eps codes wensday or thursday wen im at work I was told the scanners we have there are very similar to the tech II and regarding the wiring issue I no that the car hard a wire harness reinstall in 2010 or 2011 the windows door locks speakers ect cut out I think the dealer put in a complete harness from engine to trunk under warrenty I havent had any prblems with it till it hit maybe 65 or 67 thousand miles but now its at 71000
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
Keep us posted on all the codes when you get them.
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
ZELLERDEREK4
  • MEMBER
  • 63 POSTS
Will do if I can obtain then I gotta wait till my manager if off to pull car in again but only question I have right now is the tpms wont throw codes right?
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
Oh yeah there is tpms codes
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
ZELLDOG93
  • MEMBER
  • 111 POSTS
  • 2009 PONTIAC G6
  • 2.4L
  • 4 CYL
  • FWD
  • AUTOMATIC
  • 70,000 MILES
Found a code u2105 abs not communicating with ecm taking car to dealer for recall tomorrow morning but this isnt covered will this problem cause powersteering to cut out completely going around turns I wanna set this POS on fire its just problem after problem and seeing how its a 4 cyl its electric steering not fluid
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
So is your steering cutting out?Thats a code for no communication with the abs not steering control module.
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
ZELLDOG93
  • MEMBER
  • 111 POSTS
Yes my power steering is cutting out and was wondering if thats a related problem to the code sorry if I wasnt clear in upper statement
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
Oh ok I need you to get the power steering control module scanned codes. Get me the exact code numbers not code descriptions?The codes should start with a C you will need a professional scan tool not a diyer scan tool or a free scan at the auto parts store. You could have the dealer scan it the most common things to fail on those electric steering is the motors.
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Tuesday, October 3rd, 2017 AT 9:44 PM (Merged)
Tiny
ZELLDOG93
  • MEMBER
  • 111 POSTS
They said they couldnt find any
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Tuesday, October 3rd, 2017 AT 9:45 PM (Merged)
Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
The dealer said this?How long has it been since you lost complete power steering?If your completely loosing power steering and it says service power steering it has to be setting codes?Or your chasing a ghost.
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Tuesday, October 3rd, 2017 AT 9:45 PM (Merged)
Tiny
ZELLDOG93
  • MEMBER
  • 111 POSTS
This problem has only happened a few times since about 5600 miles car now has over 6800 and is starting to happen more frequently when this does happen you cannot turn wheel at all
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Tuesday, October 3rd, 2017 AT 9:45 PM (Merged)

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