[tuga]

The other glitch was an error message on the Detroit Diesel info center display "TPS Circuit Failed Low". A check engine light also illuminated on the dashboard. I turned off the cruise control (so that I could feel the response of the engine to the throttle) and that corrected the error. I used the cruise control for the rest of the trip with no other problems. With the manuals provided by Detroit Diesel, I was able to determing that TPS stands for throttle position sensor. Beyond that, I have no idea if this is a simple random electronic glitch that will not soon return, or if I need to have the TPS examined/replaced. Any suggestions?


Signed, a tired, stressed but happy Newell owner.[/QUOTE]

Tim,

I had the same "TPS Circuit Failed Low" message periodically for about the first 2 years that I owned the coach. I found that if I accelerated or braked, the message would clear. After a couple of years, it stopped displaying the message. I can't remember the last time it did it. I don't think that it is any reason for concern. I priced a throttle positioning sensor from Newell and it was $532 (ouch!); I didn't buy one!

I had a friend who had the same message display on his Prevost and his throttle wouldn't operate at all; he was dead in the water. He found a DD parts supply house and a parts guy found the TPS sensor (which is located under the accelerator pedal) and my friend replaced the sensor and he was on his way. The cost was about $100; I was going to buy a sensor like his but I never could get a part # for it.

I think that moisture caused some of these sensors to malfunction. Before you spend any serious money be aware that these sensors are sensative(that doesn't look like it is spelled correctly?).