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How do you know it is bad? Did you check it with a Tech 2?

Most of the times it is something else rather than the RDM

Would you please describe the problem your having and what you have tried to fix it.

People will then chime in with suggestions for things to try or how to fix the problem.
 

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Spirited driver!
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BLU SSR
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Is this the same SSR that has been thru a few owners in different far east countries and repaired using parts from other makes and models like it was stuck in Cube since the 50's ?? If so it had a BUNCH of problems that may be more than a RDM.
 

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Discussion Starter #8
How do you know it is bad? Did you check it with a Tech 2?

Most of the times it is something else rather than the RDM

Would you please describe the problem your having and what you have tried to fix it.

People will then chime in with suggestions for things to try or how to fix the problem.
I don`t have Tech2. i use Launch X431 (LAUNCH-X431)
I can connect to RDM and read it, but it have DTC error
U1017 Lost communication to engine
U1176 Lost communication to RFA
Screenshot_20191206-143036.png
Also my Bose amplifier have similar problem U1017 Lost communication to engine

both module use one data wire, i checked it all is ok. I think somebody did try to check before and probable killed it high power
 

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Usally the module you CAN communicate with is not bad. It reporting that it is not receiving a good state of health message from the modules listed. The RDM is most likely not the cause of these codes. Suspect power, ground or communication wiring to these modules or these modules may be bad.

Can you communicate with the modules listed?

Do you have access to a lab scope?

How did you check the communication wires?

I know you've posted issues in the past regarding cooling fan, and sombody hacked it pretty gound. Did you remove all non stock connections in the harness. Like i think there was an unidentified one to mass air sensor.
 

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I agree with Autoprof. From your report it appears that the RDM is operational by reporting that it is reaching out to other modules and has lost communications with them. That is not indicative of an RDM issue but with the other modules or a bad connection. I found similar, multiple lack of communications issues on another SSR and traced them to a loose connection at the data "comb" connector under the instrument panel just to the left of the steering column.
 

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Discussion Starter #12
Usally the module you CAN communicate with is not bad. It reporting that it is not receiving a good state of health message from the modules listed. The RDM is most likely not the cause of these codes. Suspect power, ground or communication wiring to these modules or these modules may be bad.

Can you communicate with the modules listed?

Do you have access to a lab scope?

How did you check the communication wires?

I know you've posted issues in the past regarding cooling fan, and sombody hacked it pretty gound. Did you remove all non stock connections in the harness. Like i think there was an unidentified one to mass air sensor.
Can you communicate with the modules listed?
I don`t have Remote control door lock receiver, Any block is ok, i can to connect.

Do you have access to a lab scope?
What you mean?

How did you check the communication wires?
I use multimeter, Check lines with power (disconnect connector and give power to wire whit lamp)

When I check the RDM and amplifier separately, I turn off all the other blocks, the errors disappear. Which is logical, since he does not see the BCM, namely, he trains all the other blocks in the car. Telling them what other blocks are present in the car.
But in the RDM unit there is a diagnostic test, for example a roof pump relay or a window relay. When you try to lower the window or roof, the unit turns off. All this leads me to think that the problem is in the RDM block, I don’t understand how it is diagnosed, but it is possible that there is a problem with the ground contacts in the block itself. Soon we will be quarantined and then I will be able to remove the unit from the car and check it on the table, applying the necessary voltage to it and connecting the diagnostic scanner.

When I checked the RDM block, I noticed one feature. When the vehicle ignition is off, the BCM sends a negative signal to the Class 2 data bus, and when the ignition is on, the signal is positive.
 

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To all sorry for the long post - I kind of got carried away.
But after spending all the time typing I am going to post it anyway, because I think there is some good information in here for all if you can read it!!!!

@Denis
Can you communicate with the modules listed?
I don`t have Remote control door lock receiver, Any block is ok, i can to connect.

So this means YOU CAN communicate with the Engine control computer (Should be PCM on 04). I would then also try a couple of things --- can you use the "bidirectional controls on the outputs from the PCM - turn on cooling fans, fuel pump, AC compressor ?
--- does the data appear to make sense?

Same for the BCM --
Can you control the door locks ??? I know there was an issue with one the buttons actually moving the mirrors -- but do they work when you try to activate with the scan tool?
Do the inputs make sense --- watch door lock input data - does it response properly to activating the button
Can you find the VIN listed in the BCM data - does it match your VIN?

Here is why I ask
GM now sends out more information regarding the loss of communication. They used to just provide a code U1000, now the last 2 digits indicates which module is at fault.

I am concerned that your scan tool is showing code u1017 and says there is a loss of communication with ECM (engine control module). 17 is the identifier for the ECM. The 04 does not use an ECM and a separate TCM (transmission control module) and you will not find this code in the 04 service manual - you will instead find U1016 where 16 is the identifier for the PCM.

When I check the RDM and amplifier separately, I turn off all the other blocks, the errors disappear. Which is logical, since he does not see the BCM, namely, he trains all the other blocks in the car. Telling them what other blocks are present in the car.

I am not sure what you are saying here. Modules (or blocks as you call them) do not train other blocks. They are pre-programed to communicate before being installed in the vehicle or after installation but basically they are programmed to read and write that language. They cannot learn a language on their own or be taught by another on board module. The same holds true for what modules should be present!

So first a short lesson on the role of the BCM

The BCM is the powermaster on all years of SSRs -- the powermaster transmits on the data line (which goes to all module on this line) which modules should be awake. Those modules then wake up and send a state of health message to all modules. If a module does not see a good state of health from a module it expects to see, it sends a signal (sets a code). IN this case both the RDM and amplifier are saying the ECM is missing.

The BCM is also the gateway module on 05 and 06 SSRs. The job of the gateway module is to translate different languages. It allows modules that talk the faster CAN language to communicate with the slower class 2 modules. The ECM and PCM on 05 & 06 modules speak CAN and the BCM is programmed differently due to this. The remaining modules are mostly identical, or at least communicate with other by speaking the slower class 2 language.

So I want to ask
You stated in a previous post you had two BCMs one showed unknown driver and another one. Do they both have the same GM part#.
Does the VIN that is displayed on your scanner match your VIN - because you have no information about the why BCM was replaced etc. I am wondering if the original BCM displayed unknown driver and a replacement BCM was installed that was not programmed specifically for your car and while it sends out a good state of health message it is confusing the information to the other modules.
Just a thought - because you/we don't know the history.

Also another point before you start dissecting a possible good RDM. You also stated:

But in the RDM unit there is a diagnostic test, for example a roof pump relay or a window relay. When you try to lower the window or roof, the unit turns off. All this leads me to think that the problem is in the RDM block, I don’t understand how it is diagnosed, but it is possible that there is a problem with the ground contacts in the block itself.

Do you know for a fact that even though your scan tool shows these tests, can they actually be performed on a properly functioning vehicle. Example: Both @shiftz33 and I recently purchased a foxwell scanner. He has had more of an opportunity to explore his than I have. But we both found one flaw. It will communicate with the RDM however it says you can activate the windows roof etc and it doesn't!!. It is also the same with the power door locks (different module). He contacted the company about this and they stated there was a software issue and are going to try and fix it with an update. SO just because the scanner says it can do something -- do you really know because it is not a "true" tech 2 that it can perform this function?

You also stated
When I checked the RDM block, I noticed one feature. When the vehicle ignition is off, the BCM sends a negative signal to the Class 2 data bus, and when the ignition is on, the signal is positive.

I am not sure what you mean by a signal, and when you say negative again what and how much? When communicating, the class 2 data line is a digital signal (rapid on/off) from about 0v to about 7volts. The on/off movement is too fast to see on a voltmeter. But is should be the same at every module on the data line and every terminal on the splice pack (when back probing) and terminal 2 of the data link connector. With the key on and engine off you should read some voltage usually around 2-3 volts DC as the meter is averaging the on/off pulses. You will also be able to pick up a frequency signal indicating that there is communication and depending on the number of modules communicating this is around 4-5 K Hz.

I also asked the following
I know you've posted issues in the past regarding cooling fan, and somebody hacked it pretty ground. Did you remove all non stock connections in the harness. Like i think there was an unidentified one to mass air sensor.
You did not reply to this

Also in another thread you stated:
The windows on both doors do not work. Passenger door lock works from a button in the cabin. The signal from the driver’s door lock is redirected to the driver’s mirror, that is, when the lock is closed and opened, the mirror is triggered. The wiring in the door and the connectors are ok, all wires are the same color. The mirrors are not controlled in the correct order, part of the functions do not work, part of the confused left and right mirrors. If I correctly understand the logic of the system, the BCM unit is responsible for these functions. Keyless access also does not work.

All of the wires are the same color! Really, did somebody rewire inside the door? What about the other door, what about the the connector behind the kick panel where the door harness plugs to body harness. The mirrors on the SSR does not go through any module!! Somebody has done something somewhere to the wiring harness!!! Maybe you should forget the computer stuff and start by fixing the mirrors, who knows you might find a spot in the harness that is screwing everything up.

Here is a somewhat decent video for those that want a little more about class 2 data education.

OH and Denis -- it shows the use of a lab scope!

 

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Discussion Starter #14
So this means YOU CAN communicate with the Engine control computer (Should be PCM on 04). I would then also try a couple of things --- can you use the "bidirectional controls on the outputs from the PCM - turn on cooling fans, fuel pump, AC compressor ?
--- does the data appear to make sense?
Yes, also PCM give me data to TCM

Same for the BCM --
Can you control the door locks ??? I know there was an issue with one the buttons actually moving the mirrors -- but do they work when you try to activate with the scan tool?
Do the inputs make sense --- watch door lock input data - does it response properly to activating the button
Can you find the VIN listed in the BCM data - does it match your VIN?
i can turn on light and any test over my diagnostic tool (launch x431)
I did`t see my Vin(
The BCM is the powermaster on all years of SSRs -- the powermaster transmits on the data line (which goes to all module on this line) which modules should be awake. Those modules then wake up and send a state of health message to all modules. If a module does not see a good state of health from a module it expects to see, it sends a signal (sets a code). IN this case both the RDM and amplifier are saying the ECM is missing.
But BCM, SIR, IPC, ABS see ECM and only two RDM and amplifier did`t see. RDM and amplifier use one wire class 2 data line

So I want to ask
You stated in a previous post you had two BCMs one showed unknown driver and another one. Do they both have the same GM part#.
Does the VIN that is displayed on your scanner match your VIN - because you have no information about the why BCM was replaced etc. I am wondering if the original BCM displayed unknown driver and a replacement BCM was installed that was not programmed specifically for your car and while it sends out a good state of health message it is confusing the information to the other modules.
Just a thought - because you/we don't know the history.
What i know both BCM has same P/N
photo_2020-04-02_12-05-32.jpg photo_2020-04-02_12-05-17.jpg photo_2020-04-02_12-05-17 (2).jpg

Now in car installed used BCM, coze has note 04 ssr.
with it BCM all work, with second BCM i have unknown driver, radio lock.
without BCM RDM show same error, with second BCM also.

I don`t know why was change BCM.

I am not sure what you mean by a signal, and when you say negative again what and how much? When communicating, the class 2 data line is a digital signal (rapid on/off) from about 0v to about 7volts. The on/off movement is too fast to see on a voltmeter. But is should be the same at every module on the data line and every terminal on the splice pack (when back probing) and terminal 2 of the data link connector. With the key on and engine off you should read some voltage usually around 2-3 volts DC as the meter is averaging the on/off pulses. You will also be able to pick up a frequency signal indicating that there is communication and depending on the number of modules communicating this is around 4-5 K Hz.
I mean when key in position RUN on BCM has + (yes i see pulse signal), but when key in position off on BCM - (ground signal)

All of the wires are the same color! Really, did somebody rewire inside the door? What about the other door, what about the the connector behind the kick panel where the door harness plugs to body harness. The mirrors on the SSR does not go through any module!! Somebody has done something somewhere to the wiring harness!!! Maybe you should forget the computer stuff and start by fixing the mirrors, who knows you might find a spot in the harness that is screwing everything up.
I fix it.

Here is a somewhat decent video for those that want a little more about class 2 data education.
Thanks
 

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@Dennis_n
I haven't forgotten you and the issues you are having with your SSR. I have been thinking about it and had a few questions that maybe you checked but just didn't post. I also had a few suggestions

Your scanner should be able to do automatic ID when you first plug it in and use it. It will then display the VIN. The Foxwell scanner will identify the VIN but, it wont let you go any further - you have to back out and enter the information separately. But it still identities the VIN correctly.

When I asked about the issue with the power mirrors your reply was
I fix it.
I am not sure what this means, did you fix it or are you going to fix it?

You also stated
But in the RDM unit there is a diagnostic test, for example a roof pump relay or a window relay. When you try to lower the window or roof, the unit turns off.
This seems like a possible issue with high resistance in the power supply or ground of the RDM, causing a reduction in current shutting it done.

Questions
Have you connected your voltmeter across the the two orange power wires on connector C3 and the black ground wire also in connector C3 while trying to operate the windows? This is actually 2 different tests - black voltmeter lead BACKPROBED into ground and Red voltmeter lead into one orange wire and then switch to other orange wire and repeat trying to operate a window. Both tests should read near battery voltage. If if drops too much you have a power supply or ground issue.

What happens when you just look at the inputs for the RDM when you attempt to operate the windows or roof from the switches on the console.? Does the input change - letting you know that RDM is receiving the command signals.

If it is receiving the inputs, change and look at outputs and see if its trying to do anything while operating the switches?

Also check live data and see if it shows window are both show "learned" in the the up and down positions.

Do your warning chimes or turn signal clicking noise work? I ask because the amplifier actually creates the sound and sends it to the left front speaker using input data from the BCM utilizing the class 2 serial data line.

You also stated
But BCM, SIR, IPC, ABS see ECM and only two RDM and amplifier did`t see. RDM and amplifier use one wire class 2 data line

One note about this -- ALL of the modules on an 03 and 04 SSR communicate (read and write information) on the SAME single wire class 2 data line.

I can't remember from your other posts --- did you check the splice pack in the the rear compartment where the RDM is. This is where splice pack SP300 is located and it splits the Class 2 data line into two parallel branches. Because they are wired in parallel they will still share the exact same information although a weak signal would get weaker.
How its wired is shown in first diagram
Location is shown in 2nd diagram (part #17)
A bad connection here could cause them both to receive and transmit poorly on the class 2 data line.

Just some things I had thought about as I did other things and I would start to think about this while working on something else.

My mind has a mind of its own and wanders sometimes.

03-04 data bus highlight RDM.gif SP300 highlight.gif
 

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Discussion Starter #16
Today I found one more SSR,
At car roof and windows work.
I installed my module to another car. My modules did`t work(

where I can to repair my module?
I found one on eBay used $1700(
 

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Denis have you checked with WIld Bills SSR Parts he has a repair service to repair them as well as used ones available on his web site. The price is much cheaper than the one for $1700.00
 

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Discussion Starter #18
Denis have you checked with WIld Bills SSR Parts he has a repair service to repair them as well as used ones available on his web site. The price is much cheaper than the one for $1700.00
Thank you.

On website WIld Bills "This rebuild service is currently unavailable. Our rebuilder is temporarily closed due to Covid-19. When the rebuilder is able to open again, we will be able to offer this service again. Thank you for your patience and understanding."

What about atcpus.com?
 

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Discussion Starter #19
I found one RDM from 2005 years, but sales say it not compatible to 2004.
If I don't mistake all module is same, correct?
 

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You can use any year. the outside temp sensor is part of the 2005/06 does not impact it's use in 2003/04
 
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