CDI Box + Ignition Coil For Honda Sportrax 400 TRX400EX 1999-2004 30410-HC4-770

CDI Box and Ignition Coil for Honda Sportrax 400 TRX400EX 1999-2004 30410-HC4-770

This CDI box and ignition coil set replaces the spark control and coil on the Honda Sportrax 400 TRX400EX from 1999 through 2004, cross-referencing OEM part 30410-HC4-770.

Overview

This CDI box and ignition coil pairing restores spark delivery on the Honda Sportrax 400 TRX400EX. The CDI module controls ignition timing while the coil steps voltage up to fire the plug, together curing no-start and weak spark faults. Riders and mechanics working on 1999 to 2004 TRX400EX quads will find this ignition set a direct-fit replacement for OEM 30410-HC4-770.

Built For Performance

• CDI module programmed with the factory timing curve for the TRX400EX
• Ignition coil wound to deliver consistent spark voltage at high rpm
• Sealed connector housing resists mud and water intrusion
• Direct plug-in to the factory harness without splicing
• Cross-references OEM part number 30410-HC4-770
• Compact housing mounts to the stock location

Fits These Machines

• for Honda Sportrax 400 TRX400EX 1999
• for Honda Sportrax 400 TRX400EX 2000
• for Honda Sportrax 400 TRX400EX 2001
• for Honda Sportrax 400 TRX400EX 2002
• for Honda Sportrax 400 TRX400EX 2003
• for Honda Sportrax 400 TRX400EX 2004

On-The-Job Use

• Diagnosing a no-spark condition on a TRX400EX
• Replacing a failed CDI after intermittent stalling
• Refreshing ignition parts during a full tune-up
• Trail or dune riding where reliable spark is critical
• Restoring a stored quad that will not fire

Specs At A Glance

Good To Know

Q: How do I tell if the CDI or the coil is at fault? A: Test the coil resistance and check for spark at the plug first, since the coil fails more often than the CDI on these quads. Replacing both at once avoids a second teardown if the other part is marginal.

Q: Will this work on a modified engine? A: It is built around the stock timing curve, so engines with aftermarket cams or big-bore kits may need a programmable unit for best results.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.