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Topic: Cruise Control & Retarder Question (Read 585 times) previous topic - next topic

Cruise Control & Retarder Question

I'm trouble shooting why my CC is not functioning. 

Has anyone had this issue that has ended up with a bad circuit in the retarder control?

No codes are coming up on the Allison diagnostics laptop.

Thanks,  pc

S/W Houston 95" U320C SE/40' 
Build #4778  Cummins M11
Repairs & Covered RV Parking (BAO)
PPL is close..

Re: Cruise Control & Retarder Question

Reply #1 –
Maybe your brake lights are on.  That would keep the cc off.

If you have a vmspc,  you can query the cruise status.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: Cruise Control & Retarder Question

Reply #2 –
Quote from: Tom Lang –
Maybe your brake lights are on.

+1 on Tom's answer.

When we bought our coach, the CC was inop.  The PO told us to check if the floor mat was stuck under the brake pedal.

It was (which kept the pedal "applied" just enough to light the brake lights).

Moved floor mat, problem solved!
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Surely, no age has been more fraught with insecurity than our own present time."

Re: Cruise Control & Retarder Question

Reply #3 –
pc,
I had intermittent CC for a year. Eventually traced to a bad connection at the engine.

Mike
2003 u295 6063

Re: Cruise Control & Retarder Question

Reply #4 –
What year/engine. Depends on control system. Mechanical cummins use old air throttle or king controls.
1998 U270 34'

Re: Cruise Control & Retarder Question

Reply #5 –
A reference was made to a CC sensor(?) in the compartment under the driver seat (i'm still looking for it.)
 
I have replaced both pneumatic brake relays (left front compartment.)
Replaced parking sensor and horn relay sensor (behind the dash.)
No.. brake lights function properly.
Replaced the throttle and cam position sensor and picked up spare's. 

Loose wire on the engine, mine is the M11 (which one was loose?)

I have not replaced the idle circuit sensor because it is not something that has
a history of being troublesome and it's not throwing a code (but it is next.)

The ECM is freshly rebuilt and the Allison is flawless (no codes.)

Just no CC and Hi-Idle.  Everything thing else is thumbs up.  pc
S/W Houston 95" U320C SE/40' 
Build #4778  Cummins M11
Repairs & Covered RV Parking (BAO)
PPL is close..

Re: Cruise Control & Retarder Question

Reply #6 –
When my cruise control wasn't working, it coincided with the first time I used my VMSpc. 

Not thinking that the VMSpc could actually tell my cruise control to disengage, I went so far as to attempt to make an appointment up near Sacramento, CA to get it fixed.  They couldn't accommodate us, so we just dealt with it.  Then, on a short trip, without the VMSpc connected, the cruise worked.  During the trip home, we tested it with the VMSpc connected, and only after I deleted that gauge from the VMSpc, the cruise worked.

Jennifer
2003 36' U295 (# 6070)
Thousand Oaks, CA

Re: Cruise Control & Retarder Question

Reply #7 –
VMS.. you might be on to something.  The PO must have had issues, mine is completely (cut) out of the loop.
Wonderful that all of the wiring to the thing is missing!!

Back to the schematic.  pc
S/W Houston 95" U320C SE/40' 
Build #4778  Cummins M11
Repairs & Covered RV Parking (BAO)
PPL is close..