BMW 3-Pin Ignition Coil Wire Harness Connector – OEM 0221504029 | Female | N52 / N53 / N54 / N55

The OEM 0221504029 is a 3-pin female connector used in BMW ignition coil harnesses. This Bosch part number identifies the connector used on BMW’s N-series inline-6 engines — N52, N53, N54, and N55. The 3-pin configuration carries coil primary power, ignition trigger signal, and coil confirmation feedback circuits. Available bare or with 15cm pre-wired leads.

Key Specifications

• OEM Part Number: 0221504029 (Bosch)
• Pin count: 3-pin
• Gender: Female
• Housing material: High-temp nylon (PA66)
• Available as: Bare connector or 15cm pre-wired leads
• Application: Ignition coil harness
• Compatible engines: BMW N52, N53, N54, N55

3-Pin Ignition Coil Circuit Assignment

• Pin 1 (B+): Coil primary power supply (+12V, ignition-switched)
• Pin 2 (IGT): Ignition trigger signal from DME (Digital Motor Electronics — BMW’s ECU)
• Pin 3 (IGF): Ignition confirmation feedback — coil sends a signal to the DME confirming each spark event

BMW N-Series Engine Guide

• N52 (2004–2015): 2.5–3.0L naturally aspirated inline-6. Used in E90/E91/E92 3 Series, E60 5 Series, E83/E70 X3/X5. Valvetronic variable valve lift.
• N53 (2007–2013): 2.5–3.0L direct injection naturally aspirated inline-6. Used in E90/E91/E92 3 Series, E60 5 Series. BMW’s first direct injection inline-6.
• N54 (2006–2016): 3.0L twin-turbocharged inline-6. Used in E90/E92 335i, E60 535i, E89 Z4 35i. High-performance applications.
• N55 (2009–2019): 3.0L single twin-scroll turbocharged inline-6. Used in F30 335i, F10 535i, F15 X5 35i. Replaced N54 in most applications.

Fault Codes This Connector Fixes

• P0351: Ignition Coil A Primary/Secondary Circuit Malfunction (Cylinder 1)
• P0352: Ignition Coil B — Cylinder 2
• P0353: Ignition Coil C — Cylinder 3
• P0354: Ignition Coil D — Cylinder 4
• P0355: Ignition Coil E — Cylinder 5
• P0356: Ignition Coil F — Cylinder 6
• P0300: Random/Multiple Cylinder Misfire Detected
• P030X: Cylinder-specific misfire (P0301–P0306)

Frequently Asked Questions

Q: My BMW has a misfire on one cylinder but the coil and spark plug test fine — is this the connector?
A: Yes. A corroded ignition coil connector causes intermittent coil trigger signal loss, which the DME interprets as a misfire even when the coil itself is functional. Swap the connector to a known-good cylinder and see if the misfire follows the connector — if it does, replace the connector.

Q: Are terminals included?
A: Yes, terminals are included with all variants.