Description
Genuine Detroit Diesel OEM rear fuel injector wiring harness (A4721506333) for the DD15 14.8L (and DD16 15.6L) engine. The harness mounts on the cylinder head and carries the injector firing signals from the ECM to the rear bank of solenoid-operated unit injectors. Heat-resistant insulation rated for the DD-series engine compartment; replace alongside the front harness (A4721506233) when injectors are removed.
Signs You Need a New Injector Harness
- Rough idle, misfires, or intermittent cylinder cutout on the rear bank
- Injector circuit fault codes (open, short, low voltage) on rear cylinders
- Visible cracking, melting, or chafe damage to harness insulation
- Corroded or loose injector connectors causing intermittent faults
Specifications
| Manufacturer | Detroit Diesel (Genuine OEM) |
|---|---|
| Part Number | A4721506333 |
| Part Type | Fuel Injector Wiring Harness, Rear Bank |
| Engine Compatibility | Detroit DD15 14.8L, DD16 15.6L |
| Mounting Location | Cylinder head, rear bank |
| Condition | New |
Cross References
This rear injector harness replaces or supersedes the following part numbers:
- Detroit Diesel: A4721506333, A4721503033, A4721501933
Companion part: The front injector wiring harness is sold separately under A4721506233 (replaces A4721502933, A4721501833). Inspect both during injector service.
Applications
This rear injector harness fits Detroit Diesel DD15 and DD16 engines installed in:
- Freightliner Cascadia, Columbia, Century, Coronado (2008–2018)
- Western Star 4700, 4800, 4900, 5700 (2009–2018)
- Sterling A-Line, L-Line (2008–2010, late production with DD15)
Verify your engine serial number and harness routing before ordering. The DD15 uses separate front (A4721506233) and rear (A4721506333) injector harnesses — confirm position before purchase.
