Operation CHARM: Car repair manuals for everyone.
Home >> GMC >> 1993 >> S15/T15 2WD P/U L4-151 2.5L >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Power Steering Pressure Switch >> Description and Operation
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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Power Steering Pressure Switch: Description and Operation

Power Steering Pressure Switch:






PURPOSE
Provides information to the ECM of increased load produced by the power steering system.

OPERATION
Turning the steering wheel increases power steering oil pressure and creates a load on an idling engine. The pressure switch will close before the load can cause an idling problem.

Closing the switch causes the circuit to report less than 1 volt to the ECM. The ECM will then increase the idle speed and retard the timing.
pro multis · About Operation CHARM