Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Power Steering Pressure Switch: Description and Operation

When hydraulic pressure reaches 3650 ± 350 kPa (530 ± 50 psi), the pressure switch closes causing the Powertrain Control Module (PCM) to actuate the idle air control valve, which increases the engine rpm to prevent the overload-induced engine speed slow down. The switch opens when hydraulic pressure drops to 3150 ± 350 kPa (460 ± 50 psi).