Owners of certain Honda Accords and Crosstours may comment that the smart start warning light comes on intermittently. DTC B12D1 (power control unit IG1B circuit error) may be set. The possible cause is a faulty under-dash sub relay box.
Affected vehicles include:
2013 Accord 2-door from VIN 1HGCT1…DA000001 through 1HGCT1…DA010212
VIN 1HGCT2…DA000001 through 1HGCT2…DA005199
2013 Accord 4-door from VIN 1HGCR2…DA000001 through 1HGCR2…DA103743
VIN 1HGCR3…DA000001 through 1HGCR3…DA022875
2013 Crosstour L4 from VIN 5J6TF3…DL000001 through 5J6TF3…DL002226
2013 Crosstour V6 from VIN 5J6TF1…DL000001 through 5J6TF1…DL001433
VIN 5J6TF2…DL000001 through 5J6TF2…DL002585
REPLACE THE UNDER-DASH SUB RELAY BOX
(Requires P/N 38330-T2A-A01)
- Remove the driver’s dash lower cover.
- Remove the driver’s dashboard undercover.
- Disconnect the under-dash sub relay box connections.
- Remove the under-dash sub relay box.
- Install the new sub relay box and reassemble.