no bus / CCD message (was: How to display error / fault codes 2001 Dodge Ram?)

From : tom lawrence

Q: ok this worked for me 2001 dodge ram short cab long box 1. ignition switch off 2. press and hold the trip reset knob 3. turn the ignition switch to on but do not start. 4. hold the reset knob for approx 10 seconds or until the word chec appears in the display then release. yes but thats the procedure for the instrument cluster diagnostic check. while that may be helpful in diagnosing the ccd bus message to display any engine-related obd-ii trouble codes cycle the ignition switch off-on-off-on-off-on and one or more pxxxx codes will display on the odometer culminating with pdone to indicate no more codes. when i turn on the ignition all the guages move. battery moves to 8 volts temp moves to 55 oil pressure moves to 0 and even the fuel guage moves a little but not to the zero or e mark. 8 volts!! lets first try a better battery that can provide the electronics with the proper voltage. no wonder nothings working right. when the pcm is fed any less than 10.5 volts strange things start to occur. .

Replies:

From : tom lawrence

does this make much sense to you tom if he is getting a no buss message doesnt that indicate that the cluster is not talking to the computer or vise-versa. yeah - that was already discussed later that same day in fact. .

From : joe brophy

on sat 29 jul 2006 172619 gmt mopar man mopar@man.com wrote ok this worked for me 2001 dodge ram short cab long box 1. ignition switch off 2. press and hold the trip reset knob 3. turn the ignition switch to on but do not start. 4. hold the reset knob for approx 10 seconds or until the word chec appears in the display then release. when i saw chec in the odo display i let go of the trip reset knob and the following numbers appeared one after another 900 920 921 940 950 999 i take it that 999 is like an end-of-code indicator. so im pretty much getting this entire laundry list 900 the ccd data bus is not operational. 1. check the ccd data bus connection at the cluster. 2. check the cluster fuses. 3. check the ccd data bus. 4. check the ccd data bus voltage. 5. check the ccd data bus terminations. 920 the cluster is not receiving a vehicle message from the pcm. 1. check the pcm software level and re-flash if required. 2. use a drb 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 re-flash if required. 2. use a drb scan tool to verify that the distance pulse message is being sent by the pcm. 940 the cluster is not receiving an airbag message from the acm 1. check the ccd data bus connections at the acm. 2. check the acm fuse. 950 the cluster is not receiving an abs lamp-on message from the cab. 1. check the ccd data bus connections at the cab 2. check the cab fuse. the truck has been parked for a few days outside and has experienced several bouts of torrential rain. i havent been able to start it since. it was running fine prior to being parked. havent had any problems with it like this since the day i bought it new march 2001. its got no leaks that im aware of. when i turn on the ignition all the guages move. battery moves to 8 volts temp moves to 55 oil pressure moves to 0 and even the fuel guage moves a little but not to the zero or e mark. i guess ill have to poke around under/behind the dash or maybe the engine compartment. if anyones got any tips id love to hear them. on my 99 durango slt 5.9l 4x4 i would get the no bus message in the trip odometer display when driving in stop and go traffic on hot days. the culprit was the pcm. it had developed a heat sensitive failure after about 30k miles. it would also shut down the vehicle and would not provide power to the coil until it had cooled off. until i replaced the pcm i would carry a five gallon can of water to pour over it if and when it began to fail. i also did the front airflow mods on the passenger side front to help airflow in the pcm mounting area as well as changing out the thermostat for a 185 degree unit per mopar performance. allpar listed several cooling mods/changes like an improved fan shroud and swapping the fan with one with more blades from a viper but mine already had those from the factory. not any further failures since the pcm was replaced. a friend who used to man the daimler help desk told me the cause of the pcm failure was hairline cracks caused from the pc board in the pcm heating up and cooling down hundreds of times eventually severing a circuit trace that would be fine until it heated up and expanded causing the trace to open slightly. the no bus error was generated because the pcm had shut down ceasing communication with any of the other controllers in the vehicle in this case the dash computer. i would also get error codes in the high 9xx range from the odometer readout. hope this helps good luck joe. .

From : tbone

ok this worked for me 2001 dodge ram short cab long box 1. ignition switch off 2. press and hold the trip reset knob 3. turn the ignition switch to on but do not start. 4. hold the reset knob for approx 10 seconds or until the word chec appears in the display then release. yes but thats the procedure for the instrument cluster diagnostic check. while that may be helpful in diagnosing the ccd bus message to display any engine-related obd-ii trouble codes cycle the ignition switch off-on-off-on-off-on and one or more pxxxx codes will display on the odometer culminating with pdone to indicate no more codes. does this make much sense to you tom if he is getting a no buss message doesnt that indicate that the cluster is not talking to the computer or vise-versa. i doubt that he will get anything this way. if he wants the diag codes i think that he will need to buy / borrow a code reader and connect to the odbii port directly. when i turn on the ignition all the guages move. battery moves to 8 volts temp moves to 55 oil pressure moves to 0 and even the fuel guage moves a little but not to the zero or e mark. 8 volts!! lets first try a better battery that can provide the electronics with the proper voltage. no wonder nothings working right. when the pcm is fed any less than 10.5 volts strange things start to occur. that sounds like a possible bad ground or bad connection between the cluster and the pcm sending bogus signals to the gauges. -- if at first you dont succeed youre not cut out for skydiving .