P1558

Code P1558, Cruise System Problem (SPS Indicated Low):

Cruise System Circuit:

CIRCUIT DESCRIPTION
The PCM controlled cruise control system is designed to monitor itself to be sure that the desired cruise position and actual cruise position are equal to each other. If the actual servo position is too low when maximum servo position is commanded, the PCM will set DTC P1558.

DTC P1558 WILL SET WHEN:
^ Throttle angle less than 50%.
^ Desired servo pos. is 90%.
^ Actual servo pos. is less than 2%.
^ Above condition for 3 seconds.

ACTION TAKEN (PCM will default to):
The PCM will disengage cruise control if a current DTC P1558 is set and C/C set speed exceeds vehicle speed by more than 8 km/h (5 mph). DTC P1558 does not illuminate the MIL (Service Engine Soon).

DIAGNOSTIC AIDS
A cruise control throttle cable which binds or intermittently sticks can cause DTC P1558 to set. Outside interference such as a CB antenna lead near the PCM wiring harness may induce a false SPS signal and set DTC P1558.

An intermittent may be caused by a poor connection, rubbed through wire insulation, or a wire broken inside the insulation.

Check for:
^ Poor connection or damaged harness Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection, and damaged harness.