Still no light on the shift pad so no start. I checked inside the Allison black plastic box located in the electrical bay. The board inside is stamped as Allison Transmission 29509439. The board has 6 Bosch high capacity 12v spdt 50 amp relays # 0332209137 attached to it. On the board there is also printing in different places which says "IGN, main power, neutral start,and reverse warning" . I cannot tell which relay might be associated with which function. Also mounted on the board are two 10amp fuses. The fusses tested O.K. for continuity and showed no voltage whether the ignition switch was on accessory or start.There are also 16 metal pins/bridges that are mounted on the board and are linked to a total of 26 wires via 4 separate plug ins. Plug in numbers 1 and 2 have a total of 14 white labeled wires with designations such as engine brake common, ignition power, engine brake out, power to reverse relay, 357 to xsm neutral, 365 ecm common, 209 reverse relay out, battery power, 232 start, 232a start,etc. The other two plug ins contain a total of12 multi colored wires and are are wrapped in tape and covered with a plastic shield. I could not read the labeling on those wires if they had any labeling. The previously mentioned 16 metal bridges were tested for voltage and they are identified on the board as a,b,c,d,e,f,g,h,j,k,l,m,n,p,r,s. With the ignition switch off none of the bridges showed any voltage. When the ignition was turned to accessory, bridge b was the only one that showed any voltage which was measured 12.6 volts. When turning the ignition switch to start, bridge b showed 12.45 volts as did bridge f. That was all the testing on that that I have been able to do so far. Any ideas on how to test this board?
I did separate the multi wire connector between the transmission selector pad and the silver metal allison box both of which are located in the transmission console in the drivers area inside the coach. I will be checking continuity on the short wire run from the pad to the connector, and hope to open the silver metal box to check for fuses, etc.
As Ed suggested I went under the coach to check the starter and starter solenoid and found that it looks like the starter itself has a total of 4 larger cables all of which are attached to the same post on the end of the starter. Not sure where they go but they showed no power. The solenoid which is mounted on top of the starter has a total of 1 larger copper colored terminal which has constant power and tested 13 amps with ignition switch off and showed no change when the ignition was turned to start. I have not been able to test the other 3 smaller yellow wires. one of the smaller yellow wires is attached to the same terminal as the larger copper colored one. Any thoughts on what, if any reading I should be able to get from the 3 other yellow solenoid wires? I also gave the solenoid a couple of hard raps with a hammer and that did not produce any results. (it felt pretty good to do that though!).
Well, I'm off to attempt to access the silver metal Allison box and also to check the wiring on the remote rear switch and the nearby compartment light switch. Can anyone advise what this switch does since there are no lights in that compartment?
Thanks,
Tom