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 C2-Range inhibit ??
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acap03
Senior Member

USA
53 Posts

Posted - 03/04/2008 :  4:21:25 PM  Show Profile  Reply with Quote
Hey,

I have a question regarding our C2's here in my county. I live in NC, if you know the specs, you may be able to answer this.

Ok, the buses are equipt with the brake interlock system (where you must depress the service brake firmly to realease the PB, and also to get the bus into gear, or to change gears).

SO, the issue is this: (only occurs on a few units, now one is out of service..having to be towed because no one knows what else to do)

The buses are not going into gear, nor is the PB releasing. During this time, the "range inhibit" light stays on..now we are all fimiliar with the range inhibitor during normal operation..but this has us stumped?? Sometimes the bus is at a turn-around..others it never leaves the parking lot. Even this morning, the bus had done its High school route and Elementary route. After dropping off at the Elem. the bus wouldnt go anywhere. Used to be after you "dumped" and pumped the air down a few times..it would usually "fix" the problem for the time. Not the case now. You try and release the PB and air just leaks out of the system, and the bus will NOT go into gear..and the "RI" light stays on...SO, the people in Highpoint apparently has told us to disconnect the heated mirrors..due to wiring issues. Unfortunatley, this step had no resolve for the problem.

The buses in question are 2008 Thomas C2's...the one that had to be towed away only has 6327 miles on it.

SO, does ANYONE know why this is happening? How we can reslove this issue? (clearly the mirror theory didnt work)

Thnx in advance!

JC Theriault
Top Member

Canada
1326 Posts

Posted - 03/04/2008 :  6:43:31 PM  Show Profile  Reply with Quote
Just out of curiousity have you attempted to shut off and restart the bus when this occurs. I had recent experiences with the lovely multiplex and computer systems on a new fleet of transit buses and pretty much every "no go into gear" or "interlock not releasing" problem was resolved by shutting down and restarting again.

Its worth a shot!

JC
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busgeek++
Advanced Member

United States
253 Posts

Posted - 03/04/2008 :  7:21:30 PM  Show Profile  Reply with Quote
A shut down and restart should help, it resets most of the electronics.

Buses are not a way of life, they are life
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acap03
Senior Member

USA
53 Posts

Posted - 03/04/2008 :  7:22:47 PM  Show Profile  Reply with Quote
Thanks for the suggestions..but to answer your question..YES, that is the first thing that is done. We tell the driver to shut the bus down and drain the tanks and start all over again. Usually doing that a few times would do the trick..now not so much. So, the usual shut the bus off and restart is not the effective solution in this case..thanks for the input though.

Edited by - acap03 on 03/04/2008 7:25:40 PM
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dem84skeeprollinup
Top Member

USA
888 Posts

Posted - 03/05/2008 :  10:31:47 PM  Show Profile  Click to see dem84skeeprollinup's MSN Messenger address  Reply with Quote
Are your transmissions equiped with pushbotton shifters by chance?

Do the world a favor and bring back GMC and Ford conventional chassis......

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acap03
Senior Member

USA
53 Posts

Posted - 03/05/2008 :  11:26:58 PM  Show Profile  Reply with Quote
NO they have the "T" handle shifters.
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rustywrench
Active Member

United States
38 Posts

Posted - 03/06/2008 :  07:51:28 AM  Show Profile  Reply with Quote
We had similar problems and found it to be the internal electrical harness for transmission wicking oil and shorting out wires. To check for this condition pull wire harness connector at transmission, should be clean and no sign of oil. If so you will need to replace internal wire harness. Warranty?
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acap03
Senior Member

USA
53 Posts

Posted - 03/06/2008 :  09:01:10 AM  Show Profile  Reply with Quote
Thank you Rusty...I have forward the message to my mechanic. Hopefully this works, now we have another C2 that started acting up this morning. Ill keep ya posted!
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acap03
Senior Member

USA
53 Posts

Posted - 03/09/2008 :  4:01:14 PM  Show Profile  Reply with Quote
Well, just an update...

Apparently it was faulty brake valves..We have replaced them and all seems to be going well. So as time goes on we shall see how things play out.

Edited by - acap03 on 03/09/2008 4:02:06 PM
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skydiverbill
Senior Member

USA
50 Posts

Posted - 03/12/2008 :  6:05:46 PM  Show Profile  Reply with Quote
yea seems like all ours needed amu #1 valves.

gravity powered fun from 13,000 feet= skydiving
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IC-CEiswhereiwannabe
Advanced Member

USA
214 Posts

Posted - 03/13/2008 :  07:07:09 AM  Show Profile  Reply with Quote
Yup, us too.

2008 C2's with brake valve issues. RI light on just about every stop and school.

New brake valves fixed it right up.

Why can't U C what I C in IC?
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Abetterchimney
Active Member

27 Posts

Posted - 02/27/2012 :  2:20:37 PM  Show Profile  Visit Abetterchimney's Homepage  Reply with Quote
Sorry to bring this post back to life but we have a 2007 Thomas C2 the range inhibt light and the check engine are on it wont turn over with the key you have to jump the starter to get it running we tried the regen process and the buss wont regen. When it was driven last (Mind you we had to jump the starter to get it running) it only had third gear and reverse and the speedo did not work. The driver also said it had been happening for week or so before the final break down it had said no transmission once and then after waiting it went away. The codes that are stuck on there now ecu 128 and BHM 164 any help would be great
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tigger2
Advanced Member

USA
446 Posts

Posted - 02/28/2012 :  05:42:08 AM  Show Profile  Click to see tigger2's MSN Messenger address  Reply with Quote
There should be more numbers possibly starting with a 1 or a 0, following the BHM 164 which is a bulkhead identifier. the same goes for the ecu 128. I know this sound simple but have you checked the back door side door and lift door for open switches, they also will cause a no start condition. I have also found several ignition switches bad the weight of junk on drivers keys will pull down on the key and cause problems, try picking up on the key and holding it straight while turning.
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Offroadwolf
Active Member

41 Posts

Posted - 02/28/2012 :  07:11:05 AM  Show Profile  Visit Offroadwolf's Homepage  Reply with Quote
Sorry, new to the site and trying to figure out how it works. Unfortunetly your 08 C2 has a problem with the park brake switch inside the air management unit (AMU). If the mechanic has replced them you should be fine. The new ones you order have been corrected, hopefully. I have swaped a lot of them out and the new style valve seems to correct the problem. The 08's were still early gen C-2's and had a few bugs, this was one of them.
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Abetterchimney
Active Member

27 Posts

Posted - 02/28/2012 :  12:15:18 PM  Show Profile  Visit Abetterchimney's Homepage  Reply with Quote
IT did have more info on the code let me get back to the shop and will post what it says then thanks for the help guys and i will try the key thing and also the door saftey latches
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Abetterchimney
Active Member

27 Posts

Posted - 02/28/2012 :  1:33:55 PM  Show Profile  Visit Abetterchimney's Homepage  Reply with Quote
The other code it had was sld 037 and sld231 fail 02
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JustinB
Advanced Member

United States
490 Posts

Posted - 02/28/2012 :  1:53:38 PM  Show Profile  Reply with Quote
From an old article I authored...

There are 3 parts to a dash diagnostic code.
- MID is the Module Identifier
- SID/PID is the System or Parameter Identifier
- FMI is the Failure or Fault Mode Idicator

The Module Identifier (MID) is the computer or brain-box that sees a problem.
Component Vendor MIDs are Engine (ECU_128), Transmission (TCU_130 only shows on EPA ’10 buses), & Anti-Lock Brake Systems (ABS_136, only shows on EPA ’02-’09 buses). Mercedes engines can show both the MCM (Motor Control Module) on the engine & the CPC (Chassis Process Controller) in the dash.
Platform MIDs are the Bulk Head Module (BHM_164), Chassis Hub Module (CHM_249), Expansion Module #1 (EXM_170), Expansion Module #2 (EXM_187) & Switch Hub Module (SHM_221).

The System Identifier (SID) or Parameter Identifier (PID) points to the circuit that the computer sees a problem with. An SID/PID number can identify both inputs & outputs. The SID/PID will need to be looked up in the shop manual specific to the Module (MID) that you have just figured out. This will either describe the system or tell you which connector & what wire coming out of that connector. Connector & Pin label diagrams can be found on the Dashboard Diagnostics document & in the workshop manual for each module.

The Failure/Fault Mode Indicator (FMI) tells you what the computer does not like about the circuit that you have just identified. You will find a listing of FMIs on the last page of the Dashboard Diagnostic document (Thomas_Shop_Rresouurces/DashBoard_Diag_EPA##). FMIs are set to an SAE standard. Each two digit indicator will mean the same type of failure no matter who’s module is flagging the failure. An FMI #03 will always mean “Voltage Above Normal or Shorted High” on any C2 platform module or any vendor module such as WabCo, Cummins or Allison

3 Minutes to getting your hands dirty:
1. Pull the 3 part code
2. Identify the Module (computer)
3. Identify the System/Parameter (connector, pin & circuit)
4. Identify the Failure Mode (behavior)

Now you know the following:
- Module, Connector & Pin of a problem
- Where that wire goes to on the bus (start to finish)
o An idea of what & where to troubleshoot
- What the system does not like about that circuit’s behavior
o An idea of how to start troubleshooting

I may not know the answer but I can usually find who does.
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Abetterchimney
Active Member

27 Posts

Posted - 02/28/2012 :  3:03:50 PM  Show Profile  Visit Abetterchimney's Homepage  Reply with Quote
The key did not work, i have checked the doors and they are all fine the codes it is pull is this
ECU 128
SLD 231
Fail 09


Then
BHM 137
SLD 037
Fail 02
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Abetterchimney
Active Member

27 Posts

Posted - 02/28/2012 :  6:18:09 PM  Show Profile  Visit Abetterchimney's Homepage  Reply with Quote
Checked all the fuses they are all good, The check engine light is on and the only way we can still start the bus is to jump it at the starter....I dont know if this has anything to with it but we tried to do the regen after we started the bus and it wont run the regen
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Abetterchimney
Active Member

27 Posts

Posted - 02/29/2012 :  09:46:04 AM  Show Profile  Visit Abetterchimney's Homepage  Reply with Quote
If i can find the problem and get it fixed, will the code reset itself or will i have to take it to a dealer to have the codes reset?
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tigger2
Advanced Member

USA
446 Posts

Posted - 02/29/2012 :  10:19:07 AM  Show Profile  Click to see tigger2's MSN Messenger address  Reply with Quote

Check you unit for communication link failure. Unhook the neg. cables from the batt including the small ones camera, radio, ect. check OHMs across pins c to d in the data link connector you should have 60 OHM's if you have 120 then an end of line resistor is bad if none you may have a broken wire. The second code bhm137 sid 037 fmi9 is a loss of communications and the top code may be as well if the trans cant tell the eng. it's in nuetral eng wont start.
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Abetterchimney
Active Member

27 Posts

Posted - 03/07/2012 :  12:36:06 PM  Show Profile  Visit Abetterchimney's Homepage  Reply with Quote
I found the problem guys it was a cracked (not blown) fuse. It had a hairline crack in it and would cause the problem to come and go. Thanks again for all your help
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Francisco Lopez III
New Member

1 Posts

Posted - 03/07/2012 :  2:41:51 PM  Show Profile  Visit Francisco Lopez III's Homepage  Reply with Quote
Have tried all that was suggested and no dice
quote:
Originally posted by Abetterchimney

I found the problem guys it was a cracked (not blown) fuse. It had a hairline crack in it and would cause the problem to come and go. Thanks again for all your help

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Abetterchimney
Active Member

27 Posts

Posted - 03/09/2012 :  1:31:34 PM  Show Profile  Visit Abetterchimney's Homepage  Reply with Quote
Francisco What is your bus doing?
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Bassman
Top Member

USA
558 Posts

Posted - 03/16/2012 :  11:10:36 AM  Show Profile  Reply with Quote
Just returning to work and saw this thread. Also, remember to watch brake light switch operation on hyd. buses. There is a recall out to replace the braklight switch. A reduction in sensitivity or intermitent switch operation can cause the original problem in this thread as well.
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