I have a '96 MD3060 in a motorhome and have a "SERVICE" code showing up in the selector window. I have ran a diagnostic check and these codes have appeared; d 1, 2 1, and 1 2. Can you tell me what the SERVICE code means and what can I do to get rid of it. Also what do the letters TPS refer to. Thanks, B.Smith

B. Smith
You can look up the scores of answers that allison man ha in his posts and probably find you answer if not post your question under allision man. That way he will see it

First of all the letters TPS stand for Throttle Position Sensor. It is a cable connected somewhere to the throttle linkage. Your code is for Tps failed low. Either your TPS needs to be adjusted or you need a new cable.
usually the connector is loose at the throttle linkage. Usually on motorhomes it is connected directly to the fuel pump lever.