fredriq skrev:
Här finns det mycket att läsa om motorer som inte startar:
http://www.sjmautotechnik.com/trouble_s … .html#hall
Distributor Hall Effect Sensor and connector (10V MC Engine)
Remove the three terminal connector from the distributor for the hall effect sensor, using a DMM check for ~12VDC, (at least 9 Volts) between terminals 1 (Red/Black wire) and 3 (Brown/Red), the two outer connector pins with the ignition key on. Pin 1 is the first terminal on the left with the spring release clip wire towards the top. The 10V Engine ECU supplies ~+12V to this hall effect connector at pins 1 and 3.
NOTE: The 20V 3B engine Hall Effect sensor will only have 4.5 to 5.5 volts between Pin 1 and 3 as the Motronic ECU only supplies approx. 5VDC to the Hall Effect Sensor
Check the connection in the plug from the hall sender on the distributor. In some cases the female contacts may be loose and are not making a good connection. Use a small dental pick to push the terminals together to ensure a good tight connection. Re-install this connector onto the distributor connection.
Use a DMM and check for low (<1.0 ohm) resistance between pin 1 and engine ground, in one case, resistance between this terminal and the ECU caused a no start condition, even though 12V was measured across pins 1 and 3.
Peel back the rubber boot on this hall sensor connector and connect a DMM to terminals 1 and 2 with the ignition key on. The voltage measured across pins 1 and 2 will be ~4 volts when the distributor hall sensor is shielded by the metal cover (hat) on the distributor shaft. The voltage should be between 0-0.5 volts when the hall sensor is not shielded by the metal hat. You can remove the distributor cap, and slowly rotate the engine around while you watch the voltage measured at pins 1 and 2.
A better test for the Hall Effect Sensor, is to make up a "low voltage" LED test light (LED with 120 ohm resistor in series) and connect the positive (+) side of the LED test light to terminal 1 (Red/Black wire) and the negative (-) side of the LED test light to terminal 2 (Green Wire) of the hall effect connector. This test is done with the connector plugged on to the distributor connector, and by pulling the rubber boot back off the connector to allow back probing the connector terminals.
The low voltage LED test light should flicker on/off when you crank the engine over during starting to indicate the hall effect sensor inside the distributor is working correctly.