Question about Roadi Rdt61 OBD2 Diagnostic Trouble Code Reader with Live Engine

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U2105 lost communication with ecm car wont start. could there be anything causing this other than ecm

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If you are getting the fault code saying that it lost communication with the ECM there could be something faulty going on with your ECU. This usually will not cause the car to not start, and will make your engine run strange or cut off while running. There can most definitely be something wrong with another component in the vehicle that would cause it to not start properly.

Posted on Oct 18, 2013

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A 2005 Ford F250 Super Duty Turbo wont start started yesterday and now won't start today the code reader on it and it gave me two codes po237 u0155 where can I find this and how can I get it fixed

code u0155 refers to lost communication with instrument panel cluster (IPC) control module
check wiring connections or replace the control module
code p 0237 refers to manifold absolute pressure (MAP) sensor AQ TC system --low input====causes ---wiring short to ground ---MAP sensor ---ECM

Jan 24, 2017 | Ford Cars & Trucks

1 Answer

My 2003 denali got coded and the codes were earased and now my truck wont start

Hooking up a scan tool to see if the PCM/ECM - engine computer will communicate should be first step . A non talking PCM would cause this problem . Who erased the codes ? Is the battery good ? Do headlamps work ? Inside lights ? Won't start how ? When you turn the key to the start position does anything happen ? When you turn the key on does the check engine light lite ?

Dec 09, 2016 | Cars & Trucks

2 Answers

I have these codes reading now po700 po335 and po727 any idea what to check first on 03 kia sorento. my car lost power then shut off, then wouldn't start

p0335 is a crank shaft sensor error. This sensor is what tells the ECM when to send spark to plugs. That is why it wont start.

Apr 02, 2016 | Kia Cars & Trucks

1 Answer

My 2004 Saturn ion 3 has 2 codes coming up u2105 p0700 an it won't go in drive or reverse what could it be

First off you need to understand your vehicle has several control modules on board . The PCM - engine computer , TCM - transmission control module , SRS - air bag module , Anti theft , antilock brakes , An these modules all are able to talk to each other on a communication network , On your vehicle it happens to be the CAN data bus !
The transmission control module (TCM) uses the controller area network (CAN) to signal the engine control module (ECM) that the TCM is requesting malfunction indicator lamp (MIL) illumination. This happens when the TCM has determined that a failure that affects emissions has occurred in the transmission control system. When the ECM receives the correct message from the TCM, DTC P0700 will set.
Which transmission does your vehicle have ?
Automatic Transaxle AF23-5
Automatic Transmission VT25-E
DTC U2105-U2199
The controller area network (CAN) serial data line is a high speed serial data bus used to communicate information between the engine control module (ECM), body control module (BCM), and the transmission control module (TCM). Typical data-transmission speeds must be high enough to ensure the required real-time response is maintained. The CAN serial data line does not communicate with the scan tool via the data link connector (DLC). CAN serial data information is interpreted by the BCM and transmitted to the serial data line by the BCM.
I suggest you take this to GM dealer or some other ASE certified repair shop .

Aug 13, 2015 | Saturn Cars & Trucks

2 Answers

What can I do when I got code u2105 in my car (Opel Astra 1600)

year, country?
this is covered in the factory service manual, "FSM".
for each code , there is a page, that tells you/ mech.
what the test is, what it does, how to do sub tests to isolate true cause.
my guess is the U code is in the cluster display?
best is to get a full scan of the car, OBD2 (EOBD?) to see all errors, all DTC. errors. then have all the facts, on errors.
lots of opel,, my guess 2007?
CAN Bus Error ECM
best i can do (no cars here usa) is above. google searching in Germany.
the car has many computer modules and one can not
communicate to the ecm(ECU/PCM) OR BCM.
is the car battery low>?
check all fuses. in car, in all fuse boxes, test them.

this is the best i can do ,no books on opel here.

Jan 03, 2015 | 2007 Opel Astra 1.6

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2004 corsa c auto wont start when warm fault codes u2103 u2104 u2105 u2107

i have a meriva and battery light comes on and spedometer drops to zero then flickers i have changed alternator and still same problem sometimes car wont start fault codes are u2105 u2103 b1484 u2104 i have been told i need repair done on ecu

Nov 20, 2013 | Vauxhall Cars & Trucks

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Code u2100- u2105

U2100 - GM Type Network - Manufacturer Controlled DTC - Manufacturer Controlled Description CAN Bus Off (4L30-E Transmission) Conditions
Cause Key on and the TCM detected a loss of communication on either Communication Area Network (CAN) Bus line for one second

U2103 - GM Type Network - Manufacturer Controlled DTC - Manufacturer Controlled Description CAN Bus Reset Counter Overrun (4L30-E Transmission)
Cause Key on and then the TCM detected a loss of communication on either CAN Bus line that exceeded 40 time out requirements

U2104 - GM Type Network - Manufacturer Controlled DTC - Manufacturer Controlled Description CAN Bus Reset Counter Overrun (4L30-E Transmission)
Cause Key on and then the TCM detected a loss of communication on either CAN Bus line that exceeded 40 time out requirements
U2105 - GM Type Network - Manufacturer Controlled DTC - Manufacturer Controlled Description CAN Bus Error ECM (4L30-E Transmission) Conditions
Cause Key on and the TCM did not receive ECM messages for 1 second

or you can ask the 24 hrs live technical support was multi-diag, they will like to help you, good luck

Aug 14, 2013 | 2005 Isuzu Ascender

1 Answer

What is code B2799

This Diagnostic Trouble Code (DTC) is output when the Engine Control Module (ECM) detects errors in communication between the Transponder Key Electronic Control Unit (ECU) assembly and the ECM, or in the communication lines. This DTC is also output when an engine start is attempted while the ECU communication ID between the transponder key ECU assembly and the ECM is different.
Possible causes Faulty Key Faulty transponder key amplifier Faulty Transponder Key Electronic Control Unit (ECU) Transponder key amplifier wire harness Faulty Engine Control Module (ECM)

Mar 02, 2013 | 2007 Lexus ES 350

1 Answer

Engine will die

There is a Communication problem between the Transmission Control Module (TCM) and the Engine control module. That is the bad news and is why it's shutting down the engine. 
The good news is i believe there is a TSB recall on the 2004 - 2007 chevy aveo for the P0700 problem so it should be covered under warranty. 
Believe the TSB# 05-06-01-030D
Good luck and hope this helps and hope it's not a bad ECM. Check the wire harness to the ECM and TCM, look for broken wire or the harness it self gone apart. 

May 24, 2009 | 2004 Chevrolet Aveo

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