An exhaust leak at the manifold or turbo flange can cause overboost codes.
You need to check the ambient and MAP sensor readings with key-on-engine-off. They should match within 0.5psi.
Just an update.. Spent 1/2 hour in the cold with my new Autel AP200 and got lots of codes.
When I go to live data I see that 3 pressure sensors all agree within 10 Millibars. Autel help screen says that is what is required (see attached.)
1.0 Atmospheric pressure =993 mB
2.0 Intake pressure = 993mB
3.0 Boost pressure = 991mB
All three readings are with ignition on, engine off.
I then went ahead and did an autoscan and got lots of codes.
On my Instrument Cluster unit I see five (5) Error Codes
B1040-000 CAN communication to the Engine control unit is faulty
B1041-000 CAN communication with the brake system module is faulty
B1042-000 CAN communication to control module electronic transmission control is faulty
B1470- Fuel level sensor has short to ground
B1010 -SRS malfunction indicator lamp is faulty
See image of scan for that module attached. Funny thing is,, my fuel gauge works just fine, and when I turn on ignition , the SRS lamp comes on, the goes off as expected.
I also get some codes from the transmission module (don't recall exactly which one).
They are
P1876 No or incorrect CAN message from ABS
P1817-002 Reversing light has short circuit to positive or open circuit.
The 1817-002 is valid, as I just checked and confirmed that the back up lamps are not coming on when I shift into reverse.
So.. now that I have all theses codes, can anyone suggest on how best to address the CAN related codes from the instrument cluster.
My current problem is when I search for P1040 I get many threads, but don't see that code in the thread. I tried searching with quotes "P1040" but that also did not improve my search results.
I have no check engine lamp , and with the exception of random LHM and the overboost code, rig is running fine.
I have also checked the cable exiting the transmission for external visible leaks or evidence of fluid and it looks perfect and dry.. and was replaced a couple of years ago as a proactive measure to prevent the leak that wicks up the wire and damages the ECU.
Last question is when I try to scan the Transmission I get "unknown version of control module" but when I scan the item above transmission (electronic transmission control) it scans that just fine.
Any ideas why the Autel AP200 wont scan my Transmission module?
Thanks in advance to all the experts
CPU