C1787: OBD-II code C1787 flags the damper control relay coil shorted to ground — the relay is stuck de-energised, cutting power to all damper actuators.

Symptoms

• The 'Service Ride Control' warning is displayed and adaptive damping is completely disabled at all four corners.
• No damper actuator can be driven because the relay never closes to supply their power feed.
• The suspension behaves as a passive system while the fault is active.

Common causes

• A chafed relay control wire shorted to chassis ground, preventing the ICCS2 module from energising the coil.
• An internally shorted relay coil that pulls the control line to ground.
• A failed ICCS2 module driver internally shorted to ground on the relay control output.

What to do?

Disconnect the damper control relay and verify the coil control wire has no continuity to ground with the relay unplugged. Measure the relay coil resistance. Repair chafed wiring or replace the relay. If wiring and relay are good, the ICCS2 module driver has failed and the module needs replacement.