Honda Odyssey Service Manual: Under-Dash Subrelay Box Test/Replacement (With Keyless Access)

The under-dash subrelay box contains these relays:

• ACC relay

• IG1A relay

• IG1B relay

• IG2 relay

1. Do the battery terminal disconnection procedure.

1. Remove the driver's middle panel.

3. Remove the bolt and under-dash subrelay box (A).

4. Disconnect the connectors (B) from the under-dash subrelay box.

5. Test each relay circuit as shown:

   ACC relay:

   There should be continuity between terminals A2 and C1 when battery power is connected to terminal B2, and body ground is connected to terminal B1.

   There should be no continuity between terminals A2 and C1 when power is disconnected.

   IG1A relay:

   There should be continuity between terminals A1 and B7 (or C3) when battery power is connected to terminal B3, and body ground is connected to terminal B1.

   There should be no continuity between terminals A1 and B7 (or C3) when power is disconnected.

   There should be continuity between terminals B7 and C3 at any time.

   IG1B relay:

   There should be continuity between terminals A2 and B6 (or C2) when battery power is connected to terminal B3, and body ground is connected to terminal B1.

   There should be no continuity between terminals A2 and B6 (or C2) when power is disconnected.

   There should be continuity between terminals B6 and C2 at any time.

   IG2 relay:

   There should be continuity between terminals A1 and B5 (or C4) when battery power is connected to terminal B4, and body ground is connected to terminal B1.

   There should be no continuity between terminals A1 and B5 (or C4) when power is disconnected.

   There should be continuity between terminals B5 and C4 at any time.

6. If any relay circuit fails the test, remove the under-dash subrelay box (A) from the bracket (B).

1. Replace the under-dash subrelay box.

1. Install the subrelay box in the reverse order of removal.

1. Do the battery terminal reconnection procedure.