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Function Test

NOTE:

Be careful not to scratch or damage the defogger wires with the tester probe.
Before testing, check the No. 53 (30A) fuse in the under-hood fuse/relay box and No. 3 (7.5A) fuse in the driver's under-dash fuse/relay box.

Check for voltage between the positive terminal (A) and body ground with the ignition switch and defogger switch ON.
There should be battery voltage.
- If there is no voltage, check for:
  - faulty defogger relay.
  - an open in the BLK/GRN wire.
  - faulty climate control panel and unit.
- If there is battery voltage, go to step 2.
Fig 1: Checking For Voltage Between The Positive Terminal & Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Check for voltage between the positive terminal (A) and negative terminal (A) and negative terminal (B).
There should be battery voltage.
- If there is no voltage, check for:
  - an open in the BLK wire.
  - poor ground (G652).
- If there is battery voltage, go to step 3.
Touch the voltmeter positive probe to the halfway point of each defogger wire, and the negative probe to the negative terminal.
There should be about 6 V with the ignition switch and the defogger switch ON.
- If the voltage is as specified, the defogger wire is OK.
- If the voltage is not as specified, repair the defogger wire.
  - If it is battery voltage, there is a break in the negative half of the wire.
  - If it is 0 V, there is a break in the positive half of the wire.