Which OBD Scanner is optimal to scan GM

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nonickatall

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Hello,

I am new to the GM World and I wonder which aftermarket scanner is best for reading codes at a Cadillac Escalate or Chevrolet Tahoe Truck? Tech2 is the original GM Software, is that correct? Is there a version, I can download and use with a USB or bluethooth OBD adapter?

I am from Germany, so i am new to real cars... ;)

So I am loking foreward for suggestion..

Thank you in advance

Ralf
 

George B

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You could do a VCXnano or an MDI clone. Otherwise Autel makes some good stuff.
The VCXnano can be tricky to get working but it has been done.

What years are the vehicles?
 
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nonickatall

nonickatall

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Thank you George...

I have a 2006 Escalate and a Friend has a 2002 Tahoe. I use Autel for german cars and I am mostly satisfied. But on the Escalate I have the feeling, that there is something weird. I can not run a comple test over all sections. I must run all test single. But that is not the problem.

What makes me wonder is, what i wrote in this thread:


quote:
So I read out the error codes and had the code:

P0455 DTC StatusCurrent DTC
Last TestFailed
This IgnitionNot Ran
MIL Requested
Since ClearedFailed

Whatever this means?!

As well, I had a lot of other errors

P0101 mass air flow Sensor performance
P0108 manifold absolute pressure sensor circuit high voltage
P0128 engine coolant temperature below Thermostat regulating temperature
P0131 HO2S circut low voltage Bank 1 Sensor 1
P0132 HO2S circut high voltage Bank 1 Sensor 1
P0133 HO2S slow response Bank 1 Sensor 1
P0134 HO2S circut insufficient activity Bank 1 Sensor 1
P0138 HO2S circut high voltage Bank 1 Sensor 1
P0140 HO2S circut insufficient activity Bank 1 Sensor 1
P0141 HO2S Heater Performance Bank 1 Sensor 2
P0151 HO2S circut low voltage Bank 2 Sensor 1
P0152 HO2S circut high voltage Bank 2 Sensor 1
P0153 HO2S slow response Bank 2 Sensor 1
P0154 HO2S circut insufficient activity Bank 2 Sensor 1
P0155 HO2S Heater Performance Bank 2 Sensor 1

Because I didn't know if these were old errors, I deleted all errors. The engine lamp was off. I drove for several days without problems. Yesterday I had the same issue again. After driving where everything was okay, I parked the car short, started the engine again and the engine lamp was on again, and didn't switch off until I deleted all errors again today.

After I deleted the codes this time, I started the engine again and checked for Error Codes again.

All codes immediately return, except:

P0455 DTC StatusCurrent DTC
Last TestFailed
This IgnitionNot Ran
MIL Requested
Since ClearedFailed

which seems to cause the engine lamp to light.

What I wonder is the following: Maybe someone can say something about..

I use a Chinese device to read the OBDII codes. This device contains all cars of the world and is mostly very helpful. What is new at GM, which I never seen at another manufacture is, I have two sections where errors are stored, like you see on the attached pic.

One is "Current&History DTC(s)" where i have the error which comes from the EVAP system and which lights the motor lamp.
And another section, which is called "Additional DTC(s)", is where i have the rest of the errors.

Does anybody has an idea where to start looking for problems,?
Because I don't think that my:
Airflow Sensor, my MAP Sensor, the coolant temperature, both Ho² Sensors are bad, but my Car runs good and had last week no issues at the exhaust gas check.
unquote:

That is why I think that there must be something wrong.
 

George B

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First thing I would do is make sure the battery is good and all the grounds are good. Then check the plug and pins for the PCM. Thats alot of codes which suggests the PCM has an issue.
 
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nonickatall

nonickatall

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Where do I find the pcm?
You don't think that this is an issue from the Autel Software?

Batterie is good and the car runs perfect...
 

MassHoe04

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The older GM may not be transmit enough data to scan tools like the Autel to run tests at all levels in one operation...
Having to test one function at a time might be a result of that communication throughput limitation.

You can buy the Tech 2 scan tool. Original can be found used (sometimes). Might be expensive...

You can buy Tech 2 clone from places like chinacardiags.com for less than $300 US that comes with optional DVD for use on tablet or laptop devices running Microsoft Windows.

While the other bi-directional scan tools (like Autel and others) allow you to test functions of many components and modules, the Tech 2 has quite a few special test functions built-in, which may be helpful.
Programming control modules for things like PassLock security module, HVAC control modules, etc. could be extremely valuable to have.

One other thing, while not necessary (but nice to have)... The GM Factory Service Manual (which you can buy digital versions of or access through online services) has step by step diagnosis tables for everything, where each row of the table has an instruction to follow using the Tech 2 scan tool and specific results you are to see in each step. The table will give the parameters you should see for that step and ask you Yes/No and guide you to the next step of the diagnosis.

While you could probably adapt the tables of diagnostic instructions to use whatever scan device you have, there are specific functions and references to things that are only available on the Tech 2.

Does any of this help sort out options for you?
 

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