1997 Pontiac Bonneville Owner's Manual - Page 281
1997 Pontiac Bonneville Manual
Page 281 highlights
Thermostat Engine coolant temperature is controlled by a thermostat in the engine coolant system. The thermostat stops the flow of coolant through the radiator until the coolant reaches a preset temperature. When to Check Power Steering Fluid It is not necessary to regularly check power steering in fluid unless you suspect there is a leak the systemor you hear an unusual noise. A fluidloss in thissystem could indicate a problem. Have the system inspected and repaired. Power Steering Fluid How To Check Power Steering Fluid When the enginecompartment is cool, unscrew the cap and wipe the dipstickwith a cleanrag. Replace the cap and completely tighten it. Then remove the cap again and look at the fluid level on the dipstick. The levelshould be at theFULL COLD mark. If necessary, add onlyenough fluid to bring the levelup to the mark. What to Use To determine what kind of fluid to use,see "Recommended Flui'dsand Lubricants" in the Index. Always use the proper fluid. Failureto use the proper fluid can causeleaks and damage hosesand seals. 6-28