ECU Cold Start

PURPOSE: Check that during the cold start phase the OCR has a fixed value of 50%

Preliminary conditions:
Coolant temperature less than 18°C.
Tachymetric relay connectors and ECU's connectors in place.

Fig. 8 Thermometer connection:

1. Connect the thermometer (-).0141BG in line between the water pump (1) and the water jacket (2), Fig. 8.
2. Start the engine. OCR value should = 50% (45° on dwell meter).
3. If OCR value is incorrect:
a. Stop the engine (key switch OFF).
b. Remove the ECU connector.

Fig. 23 ECU connector pins # 6, 12:

c. Connect an ohmmeter between terminal 12 and ground, Fig. 23. Resistance should be less than 1 ohm (coolant temperature less than 18°C).
d. If incorrect value, check the electrical circuit's continuity and the thermocontact (M853), Fig. 8.
4. If OCR value is correct:

Fig. 7 Throttle Plate Housing:

Fig. 27 Thermocontact switches:

a. Disconnect the microswitch (3), Fig. 7.
b. Check that when coolant temperature reaches 16°C to 20°C, the OCR value varies in relation to the regulation variations.
c. If not, remove the thermocontact (7), Fig. 27.
d. Place the thermocontact in a container full of water.
e. Connect an ohmmeter to its terminals.
f. Progressively heat the container and check that the resistance changes from "less than 1 ohm" (contacts closed) to "infinity" (contacts open) when the temperature reaches 16°C to 20°C.
g. If not, replace the thermocontact.
5. Reconnect the ECU connector.