E-fan conversion on a 99-06 — which harness, and why do the Nelson relays keep burning up?
Here is what the documentation says. Each point links to its source; details depend on your exact computer, harness and transmission.
Harness and power
- E38 ECM; Chevrolet Performance NA LS control kit 19171935; LS2/LS3/LS376/LS7/LSX454; 58x/4x; 2006+: ECM-controlled fan output turns on at 97 C (207 F). (Chevrolet Performance)
Other wiring
- LSx/Vortec: Current Performance's heavy-duty dual-fan add-on module uses three sealed relays and two fuses to run two fans in series at half speed first, then full speed; it has 50-amp relays, one 40-amp JCase fuse per fan, 12 AWG fan outputs, an 8 AWG main feed, and ground-triggered control wires meant to interface with PCM fan outputs. (Current Performance Wiring)
- P01 (0411); Vortec truck 4.8/5.3/6.0; 1999-2002: BP Automotive's A/C Update Kit (PN 1018) for 1999-2002 trucks screws into the Schrader valve port and lets the PCM control the electric fans when the A/C is on; it pins three wires into the PCM and requires the PCM to be programmed for fan activation. (Glenn's Auto Performance (BP Automotive reseller))
Confirm against the instructions for your exact parts before wiring. More: Harness and power in our tuning guide.
Confidence: medium — sources disagree or are limited; check the sources below.
Community discussion
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Sources
- LS Series Engine Control System Guide — Chevrolet Performance (via Scribd)
- BP Automotive Electric Fan Conversion Harness for 1999-2006 GM Truck — Glenn's Auto Performance (BP Automotive reseller)
- H.D. E-Fan Add-on Module (Sealed) — Current Performance Wiring