ECD SYSTEM Pre-heating Control Circuit

DESCRIPTION

1. DESCRIPTION

   
   

   1. When the ignition switch turns ON, the ECM calculates the glow indicator lighting time/heating corresponding to the coolant temperature at that time and turns ON the glow indicator light/glow plug relay. As the ceramics is used for a glow plug material, the current control is not performed.

      

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. DOES GLOW INDICATOR LIGHT UP

   
   

   1. Turn the ignition switch ON.

   2. Does the glow indicator light up?

   3. The glow indicator lights up for 0.5 sec. or more.

   
   

   OK

   CHECK FOR INDICATOR LIGHTING TIME AND AFTER GLOW TIME Click here

   NG

2. CHECK ECM (CHECK VOLTAGE)

   
   

   1. 

      Disconnect the ECM (E10) connector.

   2. Turn ignition switch ON.

   3. Check the voltage between terminals of the ECM connector s as shown in the table and illustration.

      Voltage
      Terminal (Positive terminal ←→ Negative terminal) Voltage GIND (E10-3) ←→ E1 (E7-22) 9 - 14 V

   
   

   OK

   CHECK AND REPLACE ECM Click here

   NG

3. CHECK FUSE (GAUGE)

   
   

   1. 

      Remove the GAUGE fuse from the R/B No. 1.

   2. Measure the continuity of the GAUGE fuse.

      Result
      Continuity

   
   

   NG

   REPLACE FUSE

   OK

4. CHECK GLOW INDICATOR LIGHT

   
   

   OK

   CHECK WIRE HARNESS

   NG

   REPLACE COMBINATION METER BULB NO. 1

5. CHECK FOR INDICATOR LIGHTING TIME AND AFTER GLOW TIME

   
   

   NG

   CHECK AND REPLACE ECM Click here

   OK

6. ARE THERE ANY DTC BEING OUTPUT

   
   

   YES

   GO TO RELEVANT DTC CHART Click here

   NO

7. CHECK GLOW PLUG RELAY ASSEMBLY

   
   
   1. 

      Text in Illustration

      *1	Ohmmeter
      *a	No Continuity
      *b	Continuity

      Remove the glow plug relay from the relay block No. 2.

   2. Inspect the glow plug relay continuity.

      
      

      1. Using an ohmmeter, check that there is no continuity between terminals 1 and 2.

      2. Check that there is continuity between terminals 3 and 4.

   3. 

      Text in Illustration

      *1	Ohmmeter
      *2	Battery
      *a	Continuity

      Inspect the glow plug relay operation.

      
      

      1. Apply battery voltage across terminals 3 and 4.

      2. Using an ohmmeter, check that there is continuity between terminals 1 and 2.

   
   

   NG

   REPLACE GLOW PLUG RELAY ASSEMBLY

   OK

8. CHECK ECM (CHECK VOLTAGE)

   
   

   1. 

      Disconnect the ECM (E10) connector.

   2. Turn the ignition switch START.

   3. Check the voltage between terminals of shown in the table and illustration.

      Voltage
      Terminal (Positive terminal ←→ Negative terminal) Voltage SREL (E10-16) ←→ E1 (E7-22) 0 - 0.3 V

   
   

   NG

   CHECK AND REPLACE ECM Click here

   OK

9. CHECK WIRE HARNESS (ECM - GLOW PLUG RELAY) (a) (GLOW PLUG RELAY - BODY GROUND) (b)

   
   

   1. 

      Check for open and short in harness and connector between ECM and glow plug relay.

      
      

      1. Remove the glow plug relay.

      2. Disconnect the ECM (E10) connector.

      3. Check the continuity between terminals of the glow plug relay (3) of R/B No. 2 and ECM connector as shown in the illustration and table.

         Standard (Check for open)
         Terminal (Glow plug relay of R/B No. 2 ←→ ECM) Standard 3 ←→ SREL (E10-16) Continuity

         Standard (Check for short)
         Terminal (ECM ←→ ECM(Ground)) Standard SREL (E10-16) ←→ E1 (E7-22) No continuity

   2. 

      Check for open and short in harness and connector between the glow plug relay and body ground.

      
      

      1. Remove the glow plug relay.

      2. Check the continuity between terminals of the glow plug relay (4) of the R/B No. 2 and body ground as shown in the illustration and table.

         Standard (Check for open)
         Terminal (Glow plug relay of R/B No. 2 ←→ Body ground) Standard 4 ←→ Body ground Continuity

   
   

   NG

   REPAIR HARNESS AND CONNECTOR

   OK

10. CHECK GLOW PLUG ASSEMBLY (CHECK RESISTANCE)

    
    
    1. 

       Text in Illustration

       *1

       Ohmmeter

       Using an ohmmeter, check that there is continuity between the glow plug terminal and ground.

       Standard resistance
       Approx. 0.72 Ω at 20°C (68°F)

    
    

    NG

    REPLACE GLOW PLUG RELAY ASSEMBLY

    OK

11. CHECK GLOW PLUG ASSEMBLY (CHECK INSTALLATION)

    
    

    NG

    TIGHTEN GLOW PLUG

    OK

12. CHECK WIRE HARNESS (GLOW PLUG - GLOW PLUG RELAY) (a) (GLOW PLUG RELAY - BATTERY) (b)

    
    

    1. 

       Check for open and short in harness and connector between the glow plug and glow plug relay.

       
       

       1. Remove the glow plug relay.

       2. Disconnect the glow plug wire.

       3. Check the continuity between terminals of the glow plug relay (2) of the R/B No. 2 and glow plug wire as shown in the illustration and table.

          Standard (Check for open)
          Terminal (Glow plug relay of R/B No. 2 ←→ Glow plug wire) Standard 2 ←→ Glow plug wire Continuity

          Standard (Check for short)
          Terminal (Glow plug wire ←→ Body ground) Standard Glow plug wire ←→ Body ground No continuity

    2. 

       Check for open and short in harness and connector between the glow plug relay and battery positive terminal wire.

       
       

       1. Remove the GLOW fuse from the R/B No. 2.

       2. Check the continuity of the GLOW fuse.

          Result
          Continuity

       3. Reinstall the GLOW fuse.

       4. Remove the glow plug relay.

       5. Disconnect the battery positive terminal.

       6. Check continuity between the terminals of the glow plug relay (1) of the R/B No. 2 and battery positive terminal wire.

          Standard (Check for open)
          Terminal (Glow plug relay of R/B No. 2 ←→ Battery) Standard 1 ←→ Battery positive terminal Continuity

    
    

    NG

    REPAIR HARNESS AND CONNECTOR

    OK

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOM TABLE Click here