High rpm waring code cat c9 in 2007 Contessa

[Bryan Beamon]

Has anybody found a solution as to why l have high rpm (2800) codes when using my jacobs exhaust brake? We have 120k on our coach and recently cat pick up this code during our last oil change. The code is 190-0.During the past 110k miles the Trans would up shift prior to generating a engine overspeed code. Any ideas?

[Steve Huber Co-Admin]

Bryan,
I'm guessing your Jake drops the tranny into 4th. This can cause high RPMs when engaging the Jake at highway speeds (e.g. 65 mph or higher). I don't have a C9, but on the 3126 in our Contessa, I would get fairly high RPMs (2400-2600 if I remember correctly)  when I engaged the PAC brake at 65 mph or higher.
Steve

[Bryan Beamon]

Steve,  the problem occurs when declining a 6 or 7% grade and we are at 35 mph and the tranmission is in 3rd gear with a destination gear of 2nd and the exhaust  brake engaged. Our rpm now exceed 2800 before up shifting to 4th gear unless l brake to slow down. This can't be normal as it did not happen in the past.

[Dave Atherton]

Bryan, the code Cat pick up for you indicates possible problems. (190-02 Loss of speed signal.)
(190-11 engine speed sensor mechanical failure ).  Breakout of 190-02 pattern of the timing ring
from the primary engine speed/timing sensor is lost without a ramp down in engine rpm's.  The
Pattern of the timing ring returns with one second of being lost.   ECM detects the above following
Conditions above.  Engine will shut down only is the primary and secondary speed/timing sensor
fail. Right your problem is with the primary speed/timing sensor.
Dave Atherton Retired Cat Mechanic

[Bryan Beamon]

Dave thanks for your imput. Do you recommend  I take the coach to Cat and have the speed timing sensor replaced,

[Dave Atherton]

Bryan, I would suggest in taking to Cat and have the primary speed sensor changed out.
the sensor does not cost much and is very easy to install. Problem location is between the air compressor and front timing cover,both sensors are connected by a metal clip with 10 MM
socket head bolt and getting at sensors is something else. Sensors are pushed in place with
a o-ring and held in place by metal clip and bolt. Location is not nice and would suggest install
both the primary and secondary speed sensors, will save cat labor from again going after
the secondary speed sensor at a later date. Dave Atherton Retired Cat Mechanic

[Bryan Beamon]

Dave thanks  again, I will manage the problem  with more brake use until I can get to Petersons in Eugene. Is there any cat dealer in Californian you recommend?

[Dave Atherton]

Bryan, the sky is not falling and if you can live with what is happening wait till you
get to Peterson Cat, they are a very good place to have repair done.  Dave

[Bryan Beamon]

Dave sounds good,thanks again