LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mercedes Benz >> 1986 >> 560SL >> Repair and Diagnosis >> Engine Performance >> System >> Cis-E System >> Component Testing >> Cold Start Valve Activation
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Cold Start Valve Activation

  1. With ignition turned off, pull plug on coolant temperature sensor. Unplug Green cable on ignition control module. Crank engine and check voltage at plug of cold start valve. Voltage should be 10 volts for about 9 seconds. If okay, test is complete. If not okay, go to step 2).
  2. Check wire from cold start valve to fuel pump relay (terminal No. 4) and ground wire to engine for continuity. Resistance should about zero ohms. If not okay, repair interruption. Go to step 3). If okay, test is complete. See Figure .
    Fig 1: Cold Start Valve Plug
    G48219
  3. With coolant temperature sensor plug disconnected, check voltage between fuel pump relay plug (terminal No. 12) and TF circuit (terminal No. 2) and engine ground. Crank engine (do not start). Voltage at terminal No. 12 should about 10 volts. Voltage at terminal No. 2 should be about 3.5-5.0 volts. If not okay, repair interruption. If okay, replace fuel pump relay. End of test.