Injector Cooling Fan

Fig. 106 Injector cooling fan wiring circuit.:

The injector cooling fan, Fig. 106, is used to cool the temperature of fuel inside the injector and gallery when the engine is stopped under high temperature conditions.

Fig. 107 Injector cooling location.(typical):

1. Check to ensure continuity exists between fan motor terminals, Fig. 107.

Fig. 108 Injector cooling fan test connections.:

2. Apply battery voltage to fan motor terminals, Fig. 108, fan motor should operate. If fan motor fails to operate, it should be replaced.

Fig. 109 Injector cooling fan timer test connections.:

3. To check fan motor timer, proceed as follows:
a. Connect a jumper between battery negative post and timer terminal No. 6. Connect one lead of test lamp to timer terminal No. 5 and other test lamp lead to battery negative post, Figs. 109. Use a 12V-3W bulb with test lamp.
b. Connect jumper wire between battery positive post and timer terminal No. 1. If test lamp is not illuminated proceed to step c. If test lamp is illuminated, replace timer.
c. Connect jumper wire between battery positive post and timer terminal No. 2, then disconnect jumper wire. Timer should operate.
d. Connect jumper wire between battery negative terminal and timer terminal No. 3. Test lamp should be illuminated. If test lamp is not illuminated, replace timer.
e. While test lamp is illuminated, connect jumper wire between timer terminal No. 2 and battery positive post. Test lamp should go out, if not, replace timer.

Fig. 111 Water temperature switch location.:

Fig. 113 Water temperature switch test.:

4. Remove temperature switch, Figs. 111, then place in a pan of water heated to approximately 194°F on 1985-86 300ZX, or 212°F on 1985-86 Maxima models, and check for continuity between switch terminals, Figs. 113. Continuity should exist at above specified temperatures. There should be no continuity below specified temperatures.