Catera V6-30L VIN R (1997) Engine Control Module: EEPROM (Page 3687)
Engine Control Module: Description and Operation
Rough Road Circuit
The ECM pulls the rough road detection signal circuit up to 5 volts and monitors the circuit voltage. The ABS Controller pulls the circuit voltage down
in proportion to the severity of the rough road detected. The ECM integrates the rough road data into the calculations used in order to detect the engine
misfire.