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Measurement of Parasitic Draw






Measurement of Parasitic Draw

Measurement of Parasitic Draw

Special Tools Required

LH41 AC/DC low current clamp meter, FLULH41A*
*: Available through the Honda Tool and Equipment Program, 888-424-6857

1. Parasitic draw check 1:

Parasitic draw check 1
-1. Make sure the battery is fully charged, and that all the vehicle's electrical accessories are turned off.
* With security, go to step 1-2.
* Without security, go to step 1-4.

-2. To make the security alarm system recognize that the door is closed, open the hood, and disconnect the hood switch 2P connector.

-3. Connect the security hood switch 2P connector terminals No. 1 and No. 2 with a jumper wire.

-4. Turn the ignition switch to ON (II).

-5. Turn the ignition switch to LOCK (0).

-6. Remove the ignition key from the ignition switch.

-7. Get out of the vehicle and close all doors securely.

-8. Lock the doors with the keyless transmitter.

-9. Make sure the individual map lights are turned off and the security alarm system is armed.

-10. Wait 20 minutes or more.

-11. Attach the LH41 AC/DC low current clamp meter (A) to the battery ground cable (B). Follow the equipment manufacturer's instructions, then measure the parasitic draw.
NOTE: If you are using a digital multimeter: go to step 2.





Is the parasitic draw 27 mA or less?
-YES- Intermittent failure, the system is normal at this time.
-NO- Go to step 3.

2. Parasitic draw check 2:

Parasitic draw check 2
-1. Check the following items before measuring:
* Set the multimeter dial to the DCA (direct current amps) range.
* Plug the red test probe into the red A (Amps) jack, and plug the black test probe into the COM jack.
* To avoid blowing an input fuse, start by setting the range above 10 A.

-2. Loosen the nut (A) from the battery negative terminal.
NOTE: Follow the instructions exactly to avoid disconnecting the battery ground cable terminal from the battery negative terminal.





-3. Connect the red (+) test lead (A) to the negative terminal (B) of the battery ground cable.





-4. Slide the negative terminal of the battery ground cable upwards from the battery negative terminal post so that it still makes contact and avoids disconnection. Then connect the black (-) test lead (C) to the battery negative terminal post.

-5. Disconnect the negative terminal (A) of the battery ground cable from the battery negative terminal.





-6. Measure the parasitic draw.
NOTE: If the measured value is over the threshold, wait 10 minutes and recheck.

Is the parasitic draw 27 mA or less?
-YES- Intermittent failure, the system is normal at this time.
-NO- Go to step 3.

3. Electrical equipment check 1:

Electrical equipment check 1
-1. Check if there are any aftermarket electrical accessories installed on the vehicle.

Are there any aftermarket electrical accessories installed?
-YES- Go to step 4.
-NO- Go to step 6.

4. Electrical equipment check 2:

Electrical equipment check 2
-1. Make sure that the aftermarket electrical accessories have been properly installed.
NOTE: Check that the harness connected with the ACC, IG1, or IG2 line is not connected with the +B line.

Are the aftermarket electrical accessories installed correctly?
-YES- Go to step 5.
-NO- Repair, reinstall, or remove the aftermarket electrical accessories, then recheck.

5. Electrical equipment check 3:

Electrical equipment check 3
-1. Disconnect the aftermarket electrical accessories one at a time.

-2. Turn the ignition switch to ON (II) and then back to LOCK (0).

-3. Get out of the vehicle and close all the doors.

-4. Wait at least 40 seconds.

-5. Measure the parasitic draw.

Is the parasitic draw 27 mA or less?
-YES- Replace or repair the aftermarket electrical accessories that reduced the parasitic draw to 27 mA or less when disconnected.
-NO- Go to step 6.

6. Parasitic draw check 3:

Parasitic draw check 3
-1. Remove the back-up fuse while the test leads are connected, and measure the parasitic draw.

Is the parasitic draw 14 mA or less?
-YES- Go to step 7.
-NO- Go to step 8.

7. Parasitic draw check 4:

Parasitic draw check 4
-1. Install the back-up fuse.

-2. Short the B-CAN line to body ground with a jumper wire while the test leads are connected.

-3. Turn the ignition switch to ON (II) and then back to LOCK (0).

-4. Get out of the vehicle and close all the doors.

-5. Wait at least 40 seconds.

-6. Measure the parasitic draw.

Is the parasitic draw 27 mA or less?
-YES- Disconnect the control units from the B-CAN circuit one at a time, perform step 3-6 above, then measure the parasitic draw. Do the input test for the control unit that reduced the parasitic draw to 27 mA or less when disconnected.
-NO- Disconnect the control units from the back-up fuse circuit one at a time, perform step 3-6 above, then measure the parasitic draw. Replace the control unit that reduced the parasitic draw to 27 mA or less when disconnected.

8. Parasitic draw check 4:

Parasitic draw check 4
-1. Remove the No. A2-1 (50 A) fuse in the under-hood fuse/relay box while the test leads are connected.

-2. Turn the ignition switch to ON (II) and then back to LOCK (0).

-3. Get out of the vehicle and close all the doors.

-4. Wait at least 40 seconds.

-5. Measure the parasitic draw.

Is the parasitic draw 27 mA or less?
-YES- Go to step 9.
-NO- Remove the fuses from the under-hood fuse/relay box one at a time, and identify the parts which excessively consume current.
-NO- If all electrical circuits are OK, check the starter system circuit.
-NO- Perform the starter performance test.

9. Parasitic draw check 5:

Parasitic draw check 5
-1. Install the No. A2-1 (50 A) fuse in the under-hood fuse/relay box.

-2. Disconnect the 7P connector from the ignition switch while the test leads are connected, and measure the parasitic draw.

Is the parasitic draw 27 mA or less?
-YES- Replace the ignition switch.
-NO- Repair a short to ground in the wire between the No. A2-1 (50 A) fuse in the under-hood fuse/relay box and ignition switch.