That is a good point. My MK V wiring harness had several inline fuses, and some of the loose wires I got with my SPI also had them. In my final installation I eliminated all in-line fuses. I have a pile of extra wires and fuses.

Jim, i had an spi that had the same issues as yours. After a while of sorting i found that there was an inline fuse in the main harness all wrapped and sitting just under the distributor on the main harness. I had never seen one before and when removed it was burnt. I ended up soldering the two wires together and wrapping them with heat shrink with no further issues.

I'll look at that wire. I have the later haynes manual that shows the relay box with the four relays and I follow it back to the lambda and then to the ECU. It shows the Lambda as switched.

I can't offer any advise on the Oxygen Sensor input or circuits- the way would be to test the oxygen sensor for open circuits.




 Just for another check= looking at the diagram:

Are you able to check the Red - that changes to Pink- into the relay box = from Fuse C8 (Passenger compartment fusebox?)

I took the cover off the relay module. Four relays. I tested all for continuity. I turned the key then pushed the starter relay. Started right up. Now I'm looking at the schematic, and the source of power comes from the ECU switched by the O2 sensor. Now here comes the problem or what I think is the problem. A  month ago, I bought an ceramic oil additive and put it in. and I think it fouled the O2 sensor. Could I be right? Last night I swapped two other relay modules on a hunch and they did not work. Hard to believe that I would have 3 bad relays.

Making Progress!  Starter's good - Other systems work - Now why no Start signal to solidonid

//s825.photobucket.com/user/mininozzle/media/Mini%20stuff/ECUdig.jpg.html

ECU diagram might helP! 

update. first, thanks to ALL who chimed in. I'm at the small wire that switches the solenoid. There is no power. The wire goes back to the relay module for a starter relay. I decided to bypass the relay with a hot wire from the battery and touch the solenoid. and it starts right up. Funny, I tried two other modules last night and they did not work. I have a third one to try before I open the  original black box.

The solenoid bypass is a good suggestion. Thinking it through, if the stepper is working, you should have some power to the computer.

We are all assuming there are enough amps in the battery. Volts are easy, and the fuel pump does not draw much. Have you tried another battery? or a jump?

I'm on it.

No starter crank ..

 Check first - Signal to the "small" wire on the starer solenoid.... Take a Test light - Hook to ground- and put the pointer on the Small terminal of the starter solenoid
  Look for    -  or have someone operate the Key. The test light should light up when 'activiating' the starter switch part...

Test that first.
_________________________

(second test) RAW test  ..   on the starter is the starter solenoid (smaller round can on the starter)   the back of that has 2 large electrical posts. One has the Large Battery wire connected. and probably a few other "red" or hot wires on the same terminal.

     Using an insulated screw driver--  Manually JUMP the electricity between the two large posts.   If the starter is good - you should hear the starter motor engage and turn the motor over, This still will diagnose the Solenoid as defective, if the signal wire is working properly

you can also jump power from the small solenid terminal - to the Large Battery terminal - and test the solenoid - if that test works - will show the solenoid is not getting start signal from key.

Dead starters- Seen it plenty!

Also sometimes some quick whaps to the starter with a hammer can pop it back in to a working position. (temporary)


Test the actual starter first.

 6464 has helped me on my suspension problem so iam returning his favor for being so nice of him to help me. I value people who has helped me in anyway they can.

the floor is yours mur.

Mini4ever. Stop giving advice on topics which you know nothing about.

Just Stop.

You have been banned multiple times. 

Either bad solenoid, or bad starter or ignition is shorted or grounding is bad.

if you have a tester,  test the starter and solenoid for continuity and ohm reading

sorry for no being clear, no crank.

Wont start.
  Do you mean it cranks over and wont fire and start running?

or do you mean you hit the key and no Engine cranking? 

 Lets answer that first and then look into what might be stopping it.

Solenoid might be bad, try to bypass it and see what happens.

just substituted two different computers . still nothing

I guess I'll substitute computers now. thanks for that tip. Jim

That box is a set of relays that then go to the computer and circuits. It could be a problem, but in my case there was a dead diode in the computer.

guys, my spi mini will not start.  I heard the fuel pump and stepper motors. Everything 's been fine of late. parked it last night, and today nothing. took the battery cable off at the starter and measured voltage 12+. checked all fuses,all ok. now I'm thinking the black box relay sitting on top of the brake master. how do I check that?  any other ideas.

I just substituted 2 different black box relays from other spi's and that did not solve my problem So I don't think that is the issue.

thanks jim