IRCM Disassembly & Reassembly



IRCM Rivet PCB Rivets



Disassembly
1.  Carefully drill off the heads of the two swaged "rivets" that hold the top of the IRCM onto the bottom. A 1/4" drill bit is the perfect size. Also the use of a drill press is highly recommended to insure precise control. You do not want to drill too deep and wind up with the drill bit in the PC board! See picture on left; note only one rivet shown, there are two to remove.
2.  Now remove the case top from the bottom/pc board assembly.
3.  Using the same technique as in step (1), carefully remove the two "rivet" heads that hold the PC board onto the metal bottom section of the IRCM. Again use care and precision. Refer to picture on right.
4.  Next remove the Torx machine screw that holds the aluminum heat sink at "Q3" to the base-plate metal tab. Then carefully remove the PC board from the metal base of the IRCM. Suggestion: put the Torx screw back into the tapped aluminum heat sink hole it was removed from to avoid misplacing it.
Reassembly
1.  Remove the Torx screw from the aluminum heatsink and properly position the PC board onto the metal IRCM bottom plate. Replace the Torx screw in the correct location but leave it loose for now.
2.  Use two small machine screws, two non-conductive washers (fiber, phenolic, or plastic), and two nuts to secure the PC board back onto the metal base plate of the IRCM. 4/40 X 3/8" machine screws are close to perfect (alternatively nylon screws and nuts could be used). Snug the nuts onto the screws. Now snug down the Torx screw that was installed in step reassembly step (1).
3.  Replace the metal cover onto the PC board/base assembly and secure it with two machine screws, washers, and nuts. Again 4/40 X 3/8" machne screws are perfect. Lock washers may be used if desired; the author used aircraft-type locking nuts.



A R T I C L E   L I N K S

IRCM Overview
Schematic & Parts List
Theory of Operation



Article text, drawings and photos © 2004 by D. Joseph Frazier and
Rustec Applied Technologies; All Rights Reserved.

DISCLAIMER
Please note that while I've been as careful as possible with this article,
it may contain mistakes. I assume no liability whatsoever for any
detrimental effects using this information may cause to you or your vehicle.