GMC 2003 Savana - Manual (Page 243)

Maintenance When Trailer Towing
Your vehicle will need service more oflen when you're
pulsing a
I nailer. See Ihe Maintenance Schedule for mone
on this. Things shat are especfslly important in traifer
Operation are automatic transmission Hu id (don't o'verfill),
engine oil, a>ie lubricant, belt, cooling systenn and
brake systerr. Each of these js covered in this manual,
and the inde« will help you find them quickly. If
you're irailering. it's a. good idea to neviaw thes^ sactions
b&fore ypu siart your trip
Check periodicaSly to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
The optional heavy-duty traiier wiring package incEudes
a sovon-wirD harness assembly al the rear of the
vehicle and a four-wire harness assembly under the iofl
hand sidn cl the instrumant pangl. The seven-wire
harness assembly is taped together and located in a
frame pocket at the driver side near left corner ot
ihc frame. The seven-wire harness includes a 30-amp
leed wire. Boih hamssses come wUhout connectors and
should be wired by a qualified electrical technician.
The technician can usa tha fpJIawing color code chart
when connecting ihe wiring harness to your traiter
and trailer brake controller.
Eeven-tAfira Hamass
• Light Green: Back-up lamps
• Brown- Parking tamps
• Yellow: Le1t sloplamp and turn signal
• Dad( Green: Right stoplamp and turn signal
• Dar1( Bluo; Use tqr electric trailer brakes
• Orange; Trailer accessory
• While (heavy gage): Ground wire
Four-Wire Harness (Trailer Brake Conlroller)
• Black: Ground
• Ped/White Stripe: Fused Ballery
• Dark Blue: Trailer Brake Feed
• Light Blue; Fused Stopr'CHMSL
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