Component Tests and General Diagnostics

EPS SOLENOID

Continuity Check

Check for continuity between solenoid valve terminals with the connector disconnected.

Current Check

1. When a dummy speed oscillator tool No. MB991139 is used, proceed as follows:
a. Set speed selection switch to zero mph.
b. Turn cruise control main switch to off, then start engine and allow to idle.
c. Set vehicle speed to 6-12 mph and ensure monitor light is flashing.
d. If light remains illuminated rather than flash, move vehicle forward .98-1.31 feet.
2. When a multi-use tester tool No. MB991269 (1989) or MB991341 (1990-92) is used, proceed as follows:
a. Connect multi-use tester to self diagnostic connector and cigarette lighter.
b. Input simulated vehicle speed, using vehicle speed signal function.
c. If simulated vehicle speed cannot be input, a message will be displayed on testers display to move vehicle forward .98-1.31 feet.

Fig. 13 EPS Solneoid Current Check:

Fig. 14 EPS Solenoid Operating Current. Galant & Sigma:

Fig. 15 EPS Solenoid Operating Current. Diamante:

3. On all models, disconnect EPS solenoid valve wiring harness connector and connect a voltmeter between the two connectors as shown, Fig. 13. Do not ground the solenoid terminal.
4. Ensure solenoid current is .9-1.1 amps with vehicle at 0 mph, Figs. 14 and 15.
5. If current does not decrease as simulated speed increases, refer to TROUBLESHOOTING.
6. On 4 speed automatic transmission models, when the multi use tester is used there will be a 3 speed hold caused by the fail safe function. Therefore, disconnect the battery ground cable for ten seconds. Never drive the vehicle with the tester connected.

EPS MODE SELECTOR SWITCH TEST

Fig. 16 EPS Mode Switch Test:

Refer to Fig. 16, for continuity test of the EPS mode selector switch.