Recently I've had several conversations with owners attempting to diagnose component failure on their motorcycles using the tests in the 1999 E-H Service Handbook. These tests can be very helpful, but there are a few mistakes and misprints that can lead to a misdiagnosis. So, let's list them as we find them.
For example; the illustration for the Idle Air Control (IAC) Valve Stepper Motor Circuit found on page 4-95 is incorrect. The written description of the test is correct.
So, measure the resistance between P9A-A and P9A-D, and P9A-B and P9A-C to find the values.
Standard is 47.7 - 58.3 ohm @ 73 F.
Of course the quick test for IAC operation is to listen and watch for the IAC Plunger to move when the ignition is cycled on and off.
Ride Safe,
Jamie
Atlantic Excelsior Henderson, llc
