B19 Check The Voltage To The Transfer Case Shift Relays Coils — Circuit 704 (Dg/Lg); B20 Check Circuit 781 (O/Lb) For Open; B21 Check Circuit 782 (Br/W) For Open; B22 Check Circuits 781 (O/Lb) And 782 (Br/W) For Short(S) To Ground - Ford Expedition 1998 Workshop Manual

1998 Expedition/Navigator Workshop Manual
B19 CHECK THE VOLTAGE TO THE TRANSFER CASE SHIFT RELAYS COILS — CIRCUIT 704 (DG/LG)
Transfer Case Shift Relays C221

B20 CHECK CIRCUIT 781 (O/LB) FOR OPEN

GEM C241

B21 CHECK CIRCUIT 782 (BR/W) FOR OPEN

B22 CHECK CIRCUITS 781 (O/LB) AND 782 (BR/W) FOR SHORT(S) TO GROUND

http://www.fordtechservice.dealerconnection.com/pubs/content/~WSWJ/~MUS~LEN/21/...
Measure the voltage between transfer case shift relays C221-5, circuit 704 (DG/LG), and ground.
Is the voltage greater than 10 volts?
Yes
GO to B20.
No
REPAIR circuit 704 (DG/LG). CLEAR the DTCs. TEST the system for normal operation.
Measure the resistance between transfer case shift relays C221-9, circuit 781 (O/LB), and GEM C241-17, circuit
781 (O/LB).
Is the resistance less than 5 ohms?
Yes
GO to B21.
No
REPAIR circuit 781 (O/LB). CLEAR the DTCs. TEST the system for normal operation.
Measure the resistance between transfer case shift relays C221-8, circuit 782 (BR/W), and GEM C241-16, circuit
782 (BR/W).
Is the resistance less than 5 ohms?
Yes
GO to B22.
No
REPAIR circuit 782 (BR/W). CLEAR the DTCs. TEST the system for normal operation.
Measure the resistance between transfer case shift relays C221-8, circuit 782 (BR/W), and ground; and between
transfer case shift relays C221-9, circuit 781 (O/LB), and ground.
Page 24 of 64
8/30/2010