DESCRIPTION
When the ignition switch is turned to the ON position, the battery voltage is applied to terminal IGSW of the ECM. The ECM MREL output signal causes a current to flow to the coil, closing the contacts of the EFI relay and supplying power to terminal +B of the ECM.
If the ignition switch is turned off, the ECM holds the EFI relay ON for a maximum of 2 seconds to allow for the initial setting of the throttle valve.
WIRING DIAGRAM

INSPECTION PROCEDURE
1 INSPECT ECM (+B VOLTAGE)

Standard voltage

2 CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND)

Standard resistance: Check for open

3 INSPECT ECM (IGSW VOLTAGE)

Standard voltage

4 CHECK FUSE (IGN FUSE)
Standard resistance: Below 1 Ω
5 CHECK HARNESS AND CONNECTOR (IGNITION SWITCH - ECM)

Standard resistance: Check for open

Check for short

6 INSPECT IGNITION SWITCH ASSEMBLY
7 CHECK FUSE (AM2 FUSE)

Standard resistance: Below 1 Ω
REPAIR OR REPLACE HARNESS OR CONNECTOR (IGNITION SWITCH - BATTERY)
8 INSPECT ECM (MREL VOLTAGE)

Standard voltage

9 CHECK FUSE (EFI NO.1 FUSE)

Standard resistance: Below 1 Ω
10 INSPECT RELAY (EFI RELAY)

Standard resistance

11 CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM)

Standard resistance: Check for open

Check for short

12 CHECK HARNESS AND CONNECTOR (EFI RELAY - ECM)

Standard resistance: Check for open

Check for short

13 CHECK HARNESS AND CONNECTOR (EFI RELAY - BODY GROUND)

Standard resistance : Check for open

REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI RELAY - BATTERY)
EVAP System
VC Output CircuitHeater relay (for rear air conditioning system)
ON-VEHICLE INSPECTION
1. INSPECT REAR HEATER RELAY
(a) Remove the rear heater relay.
(b) Measure the resistance according to the value(s) in
the table below.
Standard resistance
If the resistance is not as specified, replace the rear
heater relay. ...
Terminals of ECU
1. CHECK DISTANCE CONTROL ECU
Reference: waveform 1
HINT:
Terminal: LRDD - SGND
Gauge set: 2 V/DIV., 10 ms./DIV.
Condition: ignition switch in the ON position
Reference: waveform 2
HINT:
Terminal: LRRD - SGND
Gauge set: 2 V/ ...
Terminals of ecm
1. Ecm
Hint:
each ecm terminal's standard voltage is shown in the
table below.
In the table, first follow the information under "condition".
Look under "symbols (terminal no.)" For the terminals to
inspected. The standard voltage between the terminals
is shown under ...