K: Speedometer, Improper Operation, Aerostar

K1 CHECK SPEEDOMETER OPERATION


Is speedometer free from hesitation or sticking when accelerating or decelerating smoothly?

This may also be confirmed by performing the following test: Press and hold the RESET button on the front ofthe speedometer while turning the key to RUN. Release the RESET button.Does the pointer move freely when accelerating?


Yes

GO to K2.


No

After verifying good power and ground connection, REFER to H6. H: Speedometer/Odometer Inoperative (PSOM), Aerostar REPLACE instrument cluster. VERIFY proper operation.



K2 CHECK ODOMETER DISPLAY


The trip odometer must be currently displayed for the RESET button to work.)

If unsure about missing or extra segments perform the odometer display self-test as follows: Press and hold the reset button on the front of the speedometer while turning the key to RUN. Release the RESET button. Press and release the select button. The odometer will begin with all zeroes and step through the display test each time the select button is pushed.

Refer to PSOM Display Test Sequence below for exact display. The first digit on left does not always match other digits. Turn off the key to exit this test.









^ Are all odometer digits formed correctly (no extra or missing segments)? Do the select and reset buttons work normally?


Yes

GO to K3 (CHECK pointer).


No

REPLACE instrument cluster. VERIFY proper operation.



K3 CHECK SPEEDOMETER POINTER.


^ Does pointer jump or waver at a constant speed?


Yes

GO to K4.


No

GO to K5.



K4 CHECK RABS SPEED SENSOR RING AND SENSOR.


^ Are any of the following conditions present?

Damaged missing or bent teeth Metal chips on speed sensor open or shorted sensor Improper sensor clearance to speed sensor ring Improper gap between speed sensor and speed sensor ring


Refer to Antilock Brakes/Traction Control Systems for additional information. Antilock Brakes / Traction Control Systems


Yes

REPAIR or REPLACE as necessary. VERIFY proper operation.


No

REPLACE the instrument cluster. VERIFY proper operation.


K5 CHECK FOR STUCK POINTER


^ Is pointer stuck at upper pointer stop?


Yes

GO to K6.


No

Speedometer normal.



K6 SPEEDOMETER POINTER PROVE OUT


^ Can the pointer be brought back to the normal position by performing the following procedure?

Press and hold the RESET button on the front of the speedometer while turning the key to RUN. Release the RESET button. The pointer would normally prove out or sweep from the lower to upper pointer stop and back again. In this case the pointer will "jump back" to where it should be in the sweep and continue to sweep normally when the pointer gets to within 180 degrees of the upper pointer stop (about 35 mph).Turn off the key to exit prove out.


Yes

Speedometer normal.


No

REPLACE the instrument cluster. VERIFY proper operation.