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Headlamps Circuit Diagnosis

WARNING: This page is about a different car, the 2005 Suzuki Reno and 2005 Suzuki Forenza. However, it is still accessible from the selected car via links, so may be relevant.

Low-Beam Headlamps Are Inoperative, High-Beam Headlamps Are OK 

DIAGNOSTIC INFORMATION AND PROCEDURES

Step Action Value(s) Yes No
1 Check fuses Ef20 (left side headlamps) and Ef27 (right side headlamps).
Is fuse Ef20 or Ef27 blown?		 - Go to Step 2 Go to Step 3
2
  1. Check for a short circuit and repair if necessary.
  2. Replace the fuse.
Is the repair complete?		 - System OK -
3 Check the voltage at fuses Ef20 and Ef27.
Does the voltage available at fuses Ef20 and Ef27 equal the value specified?		 11-14V Go to Step 4 Go to Step 9
4
  1. Disconnect both headlamp connectors.
  2. Turn the headlamps ON.
  3. Select the low beams.
Does the voltage at each headlamp connector terminal 5 equal the value specified?		 11-14V Go to Step 6 Go to Step 5
5 Repair the open circuit between fuses Ef20 or Ef27 and the low beam headlamps.
Is the repair complete?		 - System OK -
6
  1. Disconnect the headlamp connectors.
  2. Connect an ohmmeter between ground and either headlamp connector terminal 6.
Is the resistance equal to the value specified?		 0 Go to Step 8 Go to Step 7
7 Repair the ground circuit.
Is the repair complete?		 - System OK -
8 Replace the faulty headlamps.
Is the repair complete?		 - System OK -
9
  1. Disconnect the headlamp switch connector.
  2. Select the low beams.
  3. Use an ohmmeter to check the continuity between terminals 6 and 5 of the headlamp switch.
Does the ohmmeter indicate the value specified?		 0 Go to Step 10 Go to Step 11
10 Replace the headlamp combination switch.
Is the repair complete?		 - System OK -
11 Repair the open circuit between fuses Ef20 and Ef27 and the headlamp switch connector terminal 5.
Is the repair complete?		 - System OK -

High-Beam Headlamps Are Inoperative, Low-Beam Headlamps Are OK 

DIAGNOSTIC INFORMATION AND PROCEDURES

Step Action Value(s) Yes No
1 Check the high-beam headlamps in the "flash-to-pass" mode.
Do the high-beam headlamps work in the "flash-to-pass" mode?		 - Go to Step 11 Go to Step 2
2 Check the voltage at the headlamp switch connector terminal 7.
Does the voltage equal the value specified?		 11-14 V Go to Step 4 Go to Step 3
3 Repair the open circuit between the headlamp switch connector terminal 7 and the fuse Ef12.
Is the repair complete?		 - System OK Go to Step 4
4 Check fuses Ef15.
Is the fuse blown?		 - Go to Step 5 Go to Step 6
5
  1. Check for a short circuit. Repair it if necessary.
  2. Replace the fuse.
Is the repair complete?		 - System OK -
6
  1. Turn the high-beam headlamps ON.
  2. Check the voltage at fuses Ef15.
Does the voltage available at fuses Ef15 equal the value specified?		 11-14 V Go to Step 7 Go to Step 12
7
  1. Turn the high-beam headlamps ON.
  2. Check the voltage at headlamp terminal 4 with high beams selected.
Does the voltage available at the headlamp connector terminal 4 equal the value specified?		 11-14V Go to Step 9 Go to Step 8
8 Repair the open circuit between fuse Ef15 and the high-beam headlamps.
Is the repair complete?		 - System OK -
9 Replace the faulty headlamps.
Is the repair complete?		 - System OK -
10
  1. Disconnect the headlamp combination switch connector.
  2. Put the switch in the high-beam position.
  3. Use an ohmmeter to check the continuity of the headlamp switch between terminals 7 and 2.

Does the ohmmeter indicate the specified value?		 0 Go to Step 12 Go to Step 11
11 Replace the headlamp combination switch.
Is the repair complete?		 - System OK -
12 Repair the open circuit between headlamp combination switch connector (terminal 2) and Ef15.
Is the repair complete?		 - System OK -

High-Beam and Low-Beam Headlamps Are Inoperative on Both Left and Right Sides 

DIAGNOSTIC INFORMATION AND PROCEDURES

Step Action Value(s) Yes No
1 Check fuses F6, Ef12, Ef20, Ef27 and Ef15.
Is any fuse blown?		 - Go to Step 2 Go to Step 3
2
  1. Check for a short circuit and repair if necessary.
  2. Replace the fuse.
Is the repair complete?		 - System OK -
3
  1. Turn the low-beam headlamps ON.
  2. Check the voltage at fuses Ef20, Ef27 and Ef15.
Does the voltage at the headlamps equal the value specified?		 11-14 V Go to Step 4 Go to Step 9
4
  1. Turn the low-beam headlamps ON.
  2. Check the voltage at the headlamp connector terminal 1.
  3. Turn the high-beam headlamps ON.
  4. Check the voltage at headlamp connector terminal 1.
Does the battery voltage available at the headlamps equal the value specified?		 11-14 V Go to Step 6 Go to Step 5
5 Repair the open circuit between fuses Ef20, Ef27 and Ef15 and the headlamps.
Is the repair complete?		 - System OK -
6 Use an ohmmeter to check between ground and each headlamp connector terminal 3.
Is the resistance equal to the specified value?		 0 Go to Step 8 Go to Step 7
7 Repair the ground circuit.
Is the repair complete?		 - System OK -
8
  1. Replace the faulty headlamps.
  2. Check the charging system to make sure that charging voltage is not excessively high.
Repair if necessary. Is the repair complete?		 - System OK -
9 Temporarily substitute the illumination relay in place of the headlamp relay.
Do the headlamps operate with the substituted relay?		 - Go to Step 10 Go to Step 11
10 Install the illumination relay in its original position, and install a new headlamp relay.
Is the repair complete?		 - System OK -
11
  1. With the headlamp relay removed, turn the headlamp switch to the low-beam position.
  2. Use an ohmmeter to check the continuity between the connector for relay terminal 85 and ground.
Does the ohmmeter indicate the specified value?		 0 Go to Step 17 Go to Step 12
12
  1. Reinstall the headlamp relay.
  2. Check the voltage at the light switch connector terminal 2.
Does the voltage equal the specified value?		 11-14 V Go to Step 14 Go to Step 13
13 Repair the open circuit between headlamp relay terminal 85 and the light switch connector terminal 2.
Is the repair complete?		 - System OK -
14
  1. Disconnect the light switch connector.
  2. Turn the headlamps to the low-beam position.
  3. Use an ohmmeter to check the continuity between terminals 2 and 3 of light switch.
Does the ohmmeter indicate the specified value?		 0 Go to Step 16 Go to Step 15
15 Replace the light switch.
Is the repair complete?		 - System OK -
16 Repair the open circuit between terminal 3 of light switch connector and ground.
Is the repair complete?		 - System OK -
17 Check the voltage at headlamp switch connector terminal 6.
Does the voltage equal the specified value?		 11-14V Go to Step 19 Go to Step 18
18 Repair the open circuit between headlamp switch connector and terminal 87 of the headlamp relay.
Is the repair complete?		 - System OK -
19
  1. Disconnect headlamp switch connector.
  2. Turn the headlamps to the low-beam position.
  3. Connect an ohmmeter between terminals 5 and 6 of headlamp switch connector. Observe the reading on the ohmmeter.
  4. Turn the headlamps to the high-beam position.
  5. Connect an ohmmeter between terminals 4 and 6 of the headlamp switch. Observe the reading on the ohmmeter.
Does the ohmmeter show the specified value for both of the tests?		 0 Go to Step 20 Go to Step 15
20 Repair the open circuit between the headlamp switch and fuses Ef20, Ef27 and Ef15.
Is the repair complete?		 - System OK -
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