2nd Gen Non-Engine/Transmission No buS Error Message

[Mick2500]

My dash died yesterday. I was coasting towards a traffic light and the gong went off. ABS light came on, Brake indicator came on and all the dials on all the analog gauges slowly dropped to 0. No buS appeared in the odometer display. Engine still runs great, never a hiccup.

I made a quick pass of dash diagnostics last night and got 900 920,921,940, 950 999 as stored errors. All the Cluster diagnostics run and all the indicators and gauges test OK. Nothing has been done to my truck for years other than oil and filter changes. With 11,378 miles, you can tell it doesn't get used much. I'm going after Joint Connector #7 today sometime to see if I can find any of the CCD signals.



I will post the 'fix' when I have it.





Mick

 

[Mick2500]

OK,

I promised a FIX Oo.

Connector C130 (in PDC) pin 17 in the PCM harness side was only making incindental contact (the female side of the pin was NOT on the male side, it was just touching the back side of the female connector).

I had to disassemble the connector and straighten the female pin so that it slid over the male pin in the dash side (in the PDC) of the connector.

This pin is CCD- and you can measure it to any of the common CCD- pins in connector C134 or C358 or Datalink pin 3 under the dash to check continuity. You can also measure the CCD bus termination resistor (120 Ohms) between pins 13 (CCD+) and pin 17 in the PDC side of C130.



Yep, I'm happy but this should have never happened. It has been like this since new but only now failed. I guess there was just enough resistance in the connection that it would not pass on the CCD- bus signal.



Mick



PS The ONLY code set was a P1698 (No CCD data from PCM)



PPS The ABS fault light will stay on until your speed sensor sees 15MPH or so. :-laf

 

[JohnMcIntyre]

Thanks for all the info/tips guys. Will be on this first thing Wednesday morning and will post my findiings here too.



JMc

 

[Jim Brewer]

OK,

Connector C130 (in PDC) pin 17 in the PCM harness side was only making incindental contact ...

Thanks Mick for posting this solution. The problem is that I'm a dolt and don't know what PCM, CCD, PDC, C130, etc. mean, much less know where they are or how to fix 'em. #ad
So I started checking connector after connector and finally disconnected, cleaned, and reconnected these three connectors.



#ad




And it solved the problem. They were somewhat oiled up and sit fairly close to the turbo, so I'm not surprised they might suffer some connection degradation.

Anyway, I have 125K miles on the truck. I've had the intermittent "NoBus" error and it has gotten worse with colder temperatures. Hopefully, this will fix it - I'll post in a few weeks about it.

 

[Mick2500]

Jim,

That is the PCM. All the connectors are defined and pictured in the service manuals.



Mick

 

[Jim Brewer]

That is the PCM. All the connectors are defined and pictured in the service manuals.

Ah Ha! Thanks. Right now I don't have the service manual - is it on line somewhere? I'll do some surfing/searching and if I find it, I'll put a link to it.



Again, thanks MUCH for your help! I know this little problem would have cost $$$ and time at a dealership.

 

[Smoakb]

Thanks for the picture and information. Same issue on 2002. Just started 2 days after changing front shocks. Very odd.

 

[KPfeiffer]

Hi Mick I am having the same problem and checked all the connections under the hood and cleaned. No luck I can't find in my service manual a discription of which connector is which and how to take apart the connectors without breaking them. I can fix the pins if I can get the connector apart. Can you tell me how to get the connector apart. What service manual do you use.

 

[dresslered]

I had the same sysmptom but it turrned out to be the self-aligning connector that the instument cluster plugs in to (per John McIntyr's suggestion). It took about 5 attempts of seating it properly and then everything came back to life. Not a problem since.

 

[KPfeiffer]

Can I reach that connector from under the dash or do I have to loosen the dash and move it out. Thanks, Keith

 

[Mick2500]

Hi Mick I am having the same problem and checked all the connections under the hood and cleaned. No luck I can't find in my service manual a discription of which connector is which and how to take apart the connectors without breaking them. I can fix the pins if I can get the connector apart. Can you tell me how to get the connector apart. What service manual do you use.

I used the factory manual. The PDC is the power distribution center where all the fuses and some relays plug in under the hood on the drivers fender.



Mick

 

[KPfeiffer]

OK Thanks I will take a look at that. Are the connectors behind the air box just a distribution center for the PCM to the appropriate devices.

 

[Mick2500]

Correct. The CANBUS signals go all over the place. You can monitor it just about anywhere in the
wiring harness. If you follow the manual, itś pretty straightforward, just time consuming.

Mick

 

[dresslered]

Ken,

If you are referring to my fix, the instrument pod just comes out after removing a couple of screws. You'll see the connect down at the bottom. Make sure all the pins are straight and seated and then really press the instrument cluster down. I believe John McIntyre did this from beneath the dash but that looked extremely difficult. Like Mick said, the CANBUS signals go all over the place so it is just a matter of finding where the break is.

 

[Mick2500]

OK Thanks I will take a look at that. Are the connectors behind the air box just a distribution center for the PCM to the appropriate devices.

Ken,

If you have no idea where the two-wire canbus circuit is broken, you can disconnect the batteries and then measure the can -(minus) wire at various places in the harness. You can do the same with the can + (plus) wires. Measuring between the Can+ and Can- anywhere in the harness should read 120 Ohms (the Canbus terminating resistor value).

Like David said, finding the break is a tedious process.

 

[dresslered]

Don't you kinda miss the days of wire-from-sensor-to-gauge?

 

[Mick2500]

Don't you kinda miss the days of wire-from-sensor-to-gauge?

Maybe just a little but then we d still be replacing plugs, points, condenser, fuel pumps every 24K miles.

 

[KPfeiffer]

OK Thanks guys I will try all of this this weekend and let you know how I make out. I have the Chrysler 1999 Dodge Ram 2500-3500 service manual and will try and find the instructions and diagrams you are talking about.

 

[dresslered]

Maybe just a little but then we d still be replacing plugs, points, condenser, fuel pumps every 24K miles.

Hmmm? I now replace lift pumps every 24k miles and front ends every 70k miles.



Good luck KPfeiffer and let us know what you find.