TM 1-1520-238-T-4 Change 5 6–11 6–6. CONTROLS AND INDICATORS (cont) 6–6 Master Caution/Warning Panel Table 6–1. Drive System Controls And Indicators (cont) Pilot Caution/Warning Panel SWITCH/INDICATOR POSITION FUNCTION OIL PSI ACC PUMP indicator AMBER Lights when main transmission accessory gearbox oil pressure is below 26–30 psi. CHIPS NOSE GRBX 2 indicator AMBER Lights when engine NGB 2 oil contains metal fragments. OIL PSI MAIN XMSN 2 indicator AMBER Lights when main transmission 2 oil system oil pressure is below 26–30 psi. OIL PSI NOSE GRBX 2 indicator AMBER Lights when oil pressure in engine NGB 2 is below 26 – 30 psi. OIL HOT NOSE GRBX 2 indicator AMBER Lights when engine NGB 2 oil temperature is above 274–294 F (134–146 C). OIL HOT MAIN XMSN 2 indicator AMBER Lights when main transmission 1 oil system temperature is above 274–294 F (134–146 C). OIL HOT MAIN XMSN 1 indicator AMBER Lights when main transmission 2 oil system temperature is above 274–294 F (134–146 C). TEMP INT indicator AMBER Lights when IGB temperature is above 274–294 F (134–146 C). TEMP TR indicator AMBER Lights when 90 gearbox temperature is above 274–294 F (134–146 C). RTR BK indicator AMBER Lights when rotor brake switch is in brake or lock position. VIB GRBX indicator AMBER Lights when IGB or TGB accelerometer reads excessive vibration. OIL HOT NOSE GRBX 1 indicator AMBER Lights when engine NGB 1 oil temperature is above 274–294 F (134–146 C). CHIPS MAIN XMSN indicator AMBER Lights when main transmission oil contains metal fragments. OIL PSI NOSE GRBX 1 indicator AMBER Lights when oil pressure in engine NGB 1 is below 26 – 30 psi. OIL PSI MAIN XMSN 1 indicator AMBER Lights when main transmission 1 oil system oil pressure is below 26–30 psi. CHIPS NOSE GRBX 1 indicator AMBER Lights when engine NGB 1 oil contains metal fragments.