YOU CAN ONLY HAVE 5 OF THESE Oo. Oo. Oo. Oo. Oo.
If the 2 and 6 are swapped you get a 0121 and there are apparently different severities of codes. With a 0121 it will not accelerate, with a low voltage code it will accelerate, just needs recalibration, etc.
If you have the APPS pot wired right but the IVS wired wrong you will get the MIL after engine start 0121. Doesn't mean your APPS pot is not right, or it needs calibration, your MS is wired wrong.
Swapped the MS wiring (blue and red) and it is fine.
I have been thinking what happened and how do we keep the same thing from happening to others. I tried painting the different wires with different color nail polish colors to help keep the right wire going to the right place. Does not work because as soon as the nail polish dries hard and the wire flexes the nail polish color paint identification you are using cracks and falls off. It does work for the connector bodies though. My APPS pot connector is red, the IVS connector is green. Who would wear green nail polish?
Then I tried using different counts of small zip ties. 1 zip tie for ground, 2 zip ties for idle, 3 zip ties for throttle. Not a bad system, but I managed to screw that up. Then I went down and bought the right color wire for the MS, black, blue, red (I get marine grade wire at West Marine because it is tinned for corrosion protection). That worked. Instead of having (WeatherHead connectors) 3 back wires with (or with out) nail polish identification, you have the correct color coded wire.
The second point I want to make is make sure you know the pattern of the connector. The bus APPS IVS is ground, idle, throttle. Not ground, idle, not idle. Not ground, idle, off idle. Ground, Idle, Throttle (dc pins 1,6,2). Right here is THE CATCH. Everything is ground, idle throttle, EXCEPT dc, The APPS harness for IVS is pin 1 GROUND, then pin 6 IDLE, then pin 2 THROTTLE, for ground, idle, throttle. The WeatherHead A, B, C for ground, idle, throttle.
Now on the Weatherhead from the MS. The MS is black ground, blue idle, red throttle so keep the pattern the same, ground, idle, throttle (WeatherHead A,B,C)
If you use the bus APPS harness the IVS is orange, blue, green. It comes out in a WeatherHead connector Orange (A), Blue (B), Green (C) guess what?, Ground, Idle, Throttle. Same pattern.
I think where I got screwed up is the picture on the side of the MS. It shows Red has contact, Blue does not have contact, and Black is common. Now is that before the switch is activated (ie as it sits in your hand) or is that after the switch is activated (you close the MS switch contacts)? Well, RED is THROTTLE (which means after the switch has relaxed (like it lays in your hand)). However the same pattern, black is ground, blue (next) is idle, and last is red is throttle. SAME PATTERN Ground, idle, throttle.
Then it is easy to take the black, blue, red (ground, idle, throttle) and mate it to a WeatherHead connector A (ground), B (idle), C (throttle).
Just keept the pattern the same, Just keept the pattern the same, Just keept the pattern the same.
One very happy camper. Bus APPS pot, ventilated APPS pot, MS IVS (with bus APPS IVS backup ready, plug and play).
Bob Weis