symptoms, no guages or overhead data.

Overhead will go through menu, just doesn't seem to have any data to show.

Odometer reads no buS

Stay with me here....
When I hold the odometer reset button in and switch the ignition on, it goes into a diagnostic "chec"

codes 900,920,921,940,950, and then 999 show. Then it just stays on 999 forever, so then I again push the odometer reset button and here is where the fun begins. It then does the following:

each little portion of the odometer numbers flash off in a progression, I'm guessing to verify that each works

then every light on the dash goes on, then off, in order, one at a time

THEN !! Every guage needle moves to about a quarter, then a half, then all the way to the right, then back to zero

then it goes into it's normal pre-start mode, and the odometer reads "no buS"

Does this tell me that the instrument cluster is ok?
Could the problem be the "brain?
What do all of the 900 series codes mean???

HELP!!!!!!

 

Check to see if the muti-plug near the underside of steering coulumn under the plastic apron might have come partially loose.
I've seen that posted before.

 

I've played with every plug I can find on the truck, along with every fuse and still nothing..
I'm afraid I may have to take it to the ******* to get reamed again... sigh,
I'm beginning to hate this truck

 

here are all the codes...

INSTRUMENT CLUSTER FAILURE MESSAGE
Message Description Correction
110 A failure has been identified in the cluster CPU, RAM, or EEPROM. 1. Replace the faulty cluster.
900 The CCD data bus is not operational. 1. Check the CCD data bus connections at the cluster.
2. Check the cluster fuses.
3. Check the CCD data bus bias.
3. Check the CCD data bus voltage.
3. Check the CCD data bus terminations.

920 The cluster is not receiving a vehicle speed message from the PCM. 1. Check the PCM software level and reflash if required.
2. Use a DRB III scan tool to verify that the vehicle speed message is being sent by the PCM.

921 The cluster is not receiving a distance pulse message from the PCM. 1. Check the PCM software level and reflash if required.
2. Use a DRB III scan tool to verify that the distance pulse message is being sent by the PCM.
940 The cluster is not receiving an airbag lamp-on message from the ACM. 1. Check the CCD data bus connections to the ACM.
Check the ACM fuse.
950 The cluster is not receiving an airbag lamp-on message from the CAB. 1. Check the CCD data bus connections to the CAB.
Check the CAB fuse.
999 An error has been discovered. 1. Record the failure message.
2. Depress the trip odometer reset button to continue the Self-Diagnostic test.



Basically, it says the cluster isn't recieving any data at all...

 

do you have the radio controls on the steering wheel?if so remove the radio and disconnect the twisted blue and white wire connector from the radio.this is connected to the data bus and will kill your dash as all instruments and the radio share the bus to the body computer...good luck

 

Is it still charging? Not sure about the 24v 2nd gen. But my 12v had the same problem and it was all related to a blown crank sensor. I talk with a mechanic and he informs me that this problem causes all the same results in cars also. Blown crank sensor will cause all sorts of issues with the brain. So check that first. Hopefully some one will chime in on what the voltages should be on each side.

 

it is the ctm

 

Whats CTM??

 

central timing module . i just had this happen to my truck and the dealer fix it and said it was ctm

 

As long as it's "no bus" all the time at least it will be able to be diagnosed. Most of the time that issue is intermittant and can be fun to find. It could be the CTM, but it could be a lot of other things too.