1993 GMC Suburban Owner's Manual - Page 175

I AM40201 We'reallfamiliarwithtrafficlightsor stop lights.Oftengreenarrowsare beingused in thelights for improvedtrafficcontrol.Onsomemultilaneroads, greenarrowslightup,indicatingthattraffic in oneormorelanescanmoveor makeaturn.Greenarrowsdon'tmean"gonomatterwhat." You'll stillneed to proceed with caution, yielding the right ofway to pedestriansand sometimes to other vehicles. Sometrafficlightsalsouseredarrows turningonred. to signifythat you muststopbefore REVERSIBLE LANE Old MULTI-LANE ROADWAY AM402015 Manycityroadsandexpressways,andevenbridges,usereversible-lane trafficcontrolduringrush hours. A red X lightabovealanemeansnodriving in thatlaneatthattime. A greenarrowmeansyoumaydrive in thatlane. book for the signs posted to warn drivers what hours and days these systemsare in effect. 4-7