355 Teves ABS help

I don't know if this is good or not. Pin 86 on the orange relay goes to the starter solenoid. At the starter itself, the resistance of the solenoid should be around 0.1 ohms, but in your test, you're using the chassis as part of the test circuit which may affect the reading. You may have a "not-so-good" earth or the plug on the starter solenoid is loose/contaminated.

 

Taking into consideration the length of wire from the relay socket to the starter solenoid terminal, the inline connectors in-between, some resistance along the earthing path from the starter motor, some resistance in the contacts of the multimeter probes etc., the reading of 2.5 to 3 Ohms means that you do not have a starter relay.

When measuring very low resistances, cheaper multimeters will always add about 0.5 Ohms to the readings, even when direct, due to resistance at the points of placing the probes, at the sockets where the probes are plugged into the multimeter and at the range switch if rotary-mechanical. I was only able to get true low resistance readings, measured directly on the subject, using a Fluke multimeter.

 

First, you need to be sure that you are reading Ohms. You said "I believe Ohms" but this is not good enough. Make sure your multimeter is set to the Ohms range and test it by connecting the probes to each other. You should get a reading of around 0.5 Ohms.

To get better and more stable resistance reading between the Orange relay pin that I marked on the picture in my post #92 and the ground, you need to keep the multimeter probes fairly tight/firm on the measuring points. The ground point needs to be a clean spot. Did you use a length of wire having a male spade terminal at one end which you plugged into the relay socket? Inserting just a stripped end of a wire may give you rather unstable readings.

The next test: Start the engine (front "boot" open) and press the brake repeatedly a number of times while listening for the sound of the ABS Pump coming "on". If it comes "on", and then stops after some tome after you have stopped pumping the brake pedal, it would mean that your Orange and Black relays are good.

 

I was thinking that the orange relay contacts might be losing contact when the vehicle is moving, so static tests might not reveal the issue. I suggested jumping the relay temporarily. It shouldn’t be an issue if the battery is ok.

In theory, the seat belt/brake warning test module shouldn’t affect the orange relay, but I don’t know if the internals in the wiring diagrams are simplified. That’s why I suggested disconnecting the module.

 

You should probably clean up your grounds on the chassis/engine. I doubt it will make any difference to your issue, though... unless your relay coil isn't attached to the starter wiring at all... and the white wire is broken and partially shorting to ground. Can you disconnect the small wire on your starter solenoid and repeat the test?

I can't remember if you tested the operation of the orange relay in-situ. Can you disconnect the starter solenoid wire (away from metal) and turn the key to start to see if the pump stops running or that the orange relay clicks?

 

I think you meant to say Miro @m.stojanovic . I was just a passenger in the process.