The extra 3d wire on Hondas is a signal for the computer to know when the clutch is engaged.
hotrodac

I like oil separator also because it increases reliability and improved efficiency, but it comes with a weight penalty. If MD uses a 28 Volt DC motor for compressor drive then my design (used for military vehicles) with a 85.7 cc swept volume, modified scroll clutch assembly, serpentine belt drive c...

Rotary wing AC ain't easy! Challenge for copters is weight control of AC so fuel load can be optimized. Highest priority is cooling of electronics. Next priority is pilot and last is Passenger comfort as the lowest priority. Parasitic energy draw of AC must be considered and will comprimise passange...

I'd completely unrap the harness cover including the heat shrink tube around the diode and check the diode and wire accidental contact per common trouble shooting practice. The diode is rated at 600 v (or better 800 volt) usually Motorola branded. Arching of the battery terminals or arc welding with...

Maybe the diode in the clutch harness on the compressor or the TPS (thermal protection switch) mounted at the rear side if the compressor housing has failed open due to reverse polarity or a negative voltage disengagement spike or back EMF from fan problems. The TPS is intended to disengage the clut...

Opportunity for improvement/learning curve for next AC service:
Evidence of a good compressor is to pump up to the PRV (pressure relief valve) pop off pressure about 420 psi (the first time) and blow out oil with leak dye and R-134a.
hotrodac

Sanden's Singapore factory makes a SD5H14 (134a version of SD508) with CCW specs. SD7V16 CCW spec is used on VW diesel CCW engines but has some past problems with frisbee clutch armature plates when the CW shaft nut unscrews due to bad torque, surface finish or shaft spline loosness. Standard SD508 ...

I documented and installed a modified Vintage Air HVAC in a 1961 Pontiac Bubble Top 389 with a Sanden SD5H14 compressor which is covered in Chapter 10 of "How to Air Condition Your Hot Rod" (book available from Vintage Air). I was able to install a adequate modern parallel flow condenser w...

Compressor built by Sanden in JAPAN with Sanden SP-10 double end capped PAG same as ND pag and similar to PAG 46 viscosity. Other applications of the SD7-B10 use only 3 oz. because the body ported compressor utilizes all suction flow through the crankcase to supply cool oil continuously directly to ...

No more validation testing focus or that type of problem solving, but AG dry lock is a really big deal. Deere has several OEM counter measure designs.
hotrodac