Service Manual

ELECTRICAL

6-2 Z580/Z589 DFI Z Master Service Manual

HowItWorks Testing

A relay is an electrically actuated switch.

1. Coil: Terminals 85 and 86 are connected to a coil.

Applying 12 volts to these terminals energizes the

coil turning it into an electromagnet.

2. Switch: Terminals 30, 87 and 87a are actually part

of a single pole, double throw (SPDT) switch. Term-

inal 30 is the common lead. The switch is spring

loaded so that 30 and 87a are connected when the

coil is not energized. When the coil is energized, the

switch is “thrown” and 30 and 87 are connected (Fig.

512).

87 87a

Fig512 DSC-2517a

Fig513 relay pin diagram

1. Disconnect the relay from the harness.

2. Verify the coil resistance between terminals 85 and

86 with a multimeter (ohms setting). Resistance

should be from 70 to 90 ohms. There should be

continuity between terminals 87a and 30.

3. Connect multimeter (ohms setting) leads to relay

terminals 30 and 87. Ground terminal 86 and apply

+12 VDC to 85. The relay should make and break

continuity between terminals 30 and 87 when 12

VDC is applied and removed from terminal 85.

4. Connect multimeter (ohms setting) leads to relay

terminals 30 and 87a. Apply +12 VDC to terminal

85. With terminal 86 still grounded, the relay should

break and make continuity between terminals 30

and 87a as 12 VDC is applied and removed from

terminal.