Along with the trials and tribulations of the DT466 EGR I have been facing we had a 05, VT365 that began running like crap and ECM codes for days. I checked all electerical connections and they were all good, clean and tight. The bus sat a few days and then it would not start at all. It tried but just did not have the power to operate the injectors. The injectors would not buzz on precycle or buzz after engine was shut down. The dreaded IDM Failure has struck!!! (Weak batteries are extremely hard on IDM's due to low voltage for the 48V requirements for the injectors). This is common knowledge in the Ford power Stroke community. (our batteries are new).
The bus was towed to an International Truck shop to be repaired and the service writer said that the IDM had failed. So they want $1300.00 give or take a few hundred to replace said IDM. When I questioned him about just the bottom board needing replaced he said that they have never heard of this before and they always replace the entire IDM. Today they call with information that they found concerning just the bottom board replacement. Seems there is a Iknow article out there with all the information on this and somewhere in the neighborhood of about 1000 IDM bottom board lying in the PDC's across the country.
So now they are just going to change out the IDM bottom board and and go from there. This prevents the need of reprogramming the IDM since the bottom board is the high voltage (48V) driver side for the injectors and the programing in on the main (mother) board of the IDM. (The IDM for the DT466 and the VT365 are the same by the way). The part should come in under $200.00.
I saw a vid on youtube of a guy checking idm voltage by removing the small cover and checking voltage on one of the 4 terminals of the idm. I checked the same terminal on a vt365 but it showed zero volts. I assume the idm for the IH is different than the one for the ford even though they look identical? Which leads me to the question how do you check voltage on an IH IDM ? Unlike the ford program I dont see it as a parameter on the IH software.