ITC-5 speed calibration failure

[cstotland]

I just replaced my A22154 triducer. The initial symptom was speed quit. Temp and depth worked fine. Speed LED on ITC-5 blinked, never went on hard. Had been working solid for two years. Replaced the sensor with a new-in-box unit (S/N 3762703).

Before connecting the new one, I cut off all but ten feet of wire from the old sensor, crimped on some 1/8" lugs, and reconnected the original to see if it was possibly the cable that had gone bad. (two year old install). To my surprise, everything came up hard lit, but the speed display was indicating about 40 kts speed. Boat is in slip. Hard to hit 40 in a sailboat there or anywhere. Thought, "OK, so it's really messed up". So, I disconnected it, and hooked up the new one. The new one came up at 80kts (bounces around a bit...70...75...90...80, etc.). I used the I70 (which previously didn't "see" the old speed xducer at all when it quit), reset to factory, and tried the calibration. I am able to go "up" to a bit over 90Kts, and down to about 48kts. At those points the up/down arrows disappear, so it appears the calibration function is operating correctly, and it's the auto-zero that isn't.

anything else I can do besides send the ITC-5 back for repair?