Sunrise Medical 931157 Understanding VSI Controller Diagnostics Codes cont, Test Left Motor Short

Understanding VSI Controller Diagnostics Codes (cont.)

3.3 Three Bars - Left Motor Wiring Trip

The left hand motor has a short circuit to a battery connection.

Test Left Motor Short

Check that the batteries are fully charged and in good con- dition; and check all cables and connections. Check the connections to the left motor, look for a loose or damaged connector. Take a resistance reading from pin 3 to pin 9 and pin 3 to pin 7 or pin 8, see (figure A3.3.1) and (A3.3.2), if the all the circuits are open (resistance is greater than 10 K ohm), then replace the controller. If the reading is short (resistance is less than 10 K ohm), proceed to check the 4-pin motor connector.

A3.3.1

A3.3.2

If the all the circuits are open (resistance is greater than 10 K ohm), then replace the controller.

Measure the resistance from the bottom contact of the red thick wire on the 4-pin left motor connector to each of the top contacts of the connector see (figure A3.3.3). Measure the resistance from the bottom contact of the black thick wire on the 4-pin left motor connector to each of the top contacts of the connector see (below right). If all of the readings are open, then replace the main harness. If any of the readings are short, then replace the left motor.

Test 1

A3.3.3

Test 2

Test 3 Test 4

If all of the readings are open, then replace the main harness. If any of the readings are short, then replace the left motor.

SUNRISE MEDICAL ASPIRE SERVICE MANUAL 2003 PAGE 6