03DelcoRemy Diagnostic Manual130004222020

Page 22 S E C T I O N V Appendix 5-1. Smart IMS or SIMS Diagnostic Steps The Smart Starter with integrated magnetic switch (IMS) relay and integrated over crank protection (IOCP) is designed to protect the vehicle system from multiple system-related failures. The Smart Starter will accomplish this by not allowing the starter system to function in detrimental conditions to the starter or electrical system. To troubleshoot, you must first verify that the vehicle is equipped with the Smart Starter SIMS relay and integrated OCP. The SIMS relay is programmed to protect the vehicle from these failure modes: • Starter engagement monitor/auto start retry – click no crank or prolong power • Running engine lockout – engagement into running engine • System low/high voltage lockout – over crank and pinion chatter • Time limited crank – over crank • Auto disengage at engine start – extended overrun • Integrated OCP thermal cutout switch – heat damage from extended crank VISUAL DIFFERENCES STANDARD IMS RELAY SIMS RELAY When troubleshooting a vehicle system equipped with SIMS/IOCP, voltage and temperature are critical during diagnosis: ENGAGEMENT MONITOR/AUTO RETRY – 12-VOLT SYSTEM: The system will attempt to engage the pinion three times in less than one second. After three failed attempts, cycle the engine ignition off/on before making another crank attempt. LOW VOLTAGE LOCKOUT – 12-VOLT SYSTEM: Start attempts are not allowed if open circuit voltage is less than 12 volts (equal to 25% of the battery’s state of charge). Check system voltage and charge batteries if this condition is present before removing starter. HIGH VOLTAGE LOCKOUT – 12-VOLT SYSTEM: If starter sees system voltage of greater than 14 volts, the SIMS/ IOCP will lock out, preventing the start attempt. This protects against high voltage jumpstarts (starter will be locked out if attempting jumpstarts above 14 volts). INTEGRATED OVER CRANK PROTECTION – 12-VOLT SYSTEM: If the starter is continuously cranked and reaches an internal temperature greater than 150˚C, the OCP switch will open and abort the start attempt. This allows the starter to cool down and the OCP to close so that the crank cycle can be performed. Allow the starter to cool before removing from the vehicle. Note: When troubleshooting the starting system, verify that there is suitable voltage at the “S” terminal before removing the starter. The SIMS unit may be protecting the starting system if voltages are either high or low, or if over-cranking occurs and the OCP switch opens due to high temperatures. CAUTION LABEL Caution label to be placed on can of SIMS unit CAUTION – SMART STARTER! SMART IMSWITH IOCP EQUIPPED (INTEGRATED OVER CRANK) PREVENTS CRANKING UNDER LOW/HIGH VOLTAGE AND HIGH TEMPERATURE CONDITIONS