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Discussion Starter · #1 ·
While waiting for pressure tes

While waiting for pressure testing equipment, I proceeded to check electrical functions.

With safety circuit disconnected, ignition on, I get no voltage at the thermotime switch connector.....with no power here, the cold start injectors won't work........may be my problem. Power to the TTS comes from the start valve relay (#86 term). Power comes to the start valve relay (#30 terminal) from the fuel pump relay (#87 term). This comes from fuse #3. It seems that all should have power with ignition on.

There is direct power from the fuse, to #87 of the FP relay, then it continues to #30 and #85 of the start valve relay. #86 connects with #85. Hence, one should have power to the TTS!!!

I get 12V at term #87 of the FP relay board, but NO power at term #30 and #85 of the start valve relay board. These two should have a common 12V supply, according to the elec. diagram.
 
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Discussion Starter · #2 ·
Well, after removing the floor

Well, after removing the floor relay board, I did some testing. I found out that the 12V was at term #87a and NOT #87. The power coming in from #3 fuse only comes on as the engine cranks, not with the ignition just on.....even with the safety circuit disconnected. The power goes to #87, of the fuel pump relay, then energizes term(s) #30, and #85 of the start valve relay........this then sends a signal to the cold start valves (injectors), and the thermotime switch, via term #87 and #86 respectively. This system has nothing to do with the safety circuit. It can even be tested without the fuel pump fuses in place.

My next step is to test the relays. I plan on using a 12V source and connect it to term #85 and #86, of the relay. This will energize the electromagnet and bring continuity between term #30 and #87. This is true, it appears, for all of the relays

I am getting to really understand this stuff!!!!
 
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Discussion Starter · #3 ·
LOL ! I know who I'm call

LOL ! I know who I'm calling when I have electrical troubles! Automotive electricals have been a total mystery for me, I manage to do simple things, but that's about it. It sounds very rewarding to me, the good work your doing on your Boxer. Way to go Henry!
 
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Discussion Starter · #4 ·
Jeff: I am developing testing

Jeff: I am developing testing techniques for the various sensors. I already tested the thermotime switch..........in the kitchen. Watched the Ohm reading change as I heated it up in hot water. Will now put 12V to it and check for change in continuity.

The auxillary air valve is in the freezer, as we talk. I will do a visual and ohm check on it. Then it goes into the oven......will recheck the visual and ohm. I will then apply 12V to it and watch the opening close, as I time it.

The testing of the warm up regulator will be next.

Tomorrow, I will be working on the TR. I will check the continuity of the 25-pin FI plugs to the various sensors on the engine.
 
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Discussion Starter · #5 ·
Another way to test the TTS is

Another way to test the TTS is continuity to the engine from W and you can put a test light between W and the + on the battery and if it lights you know it grounds.
I just went through my TTS and CSI in a lengthy way.
I had a TTS that showed proper ohmage, all grounds seemed to check out, continuity when cold, none when warm, but still didn't spray the CSI. After some gentle tapping, etc. it works fine. Anyway, just thought I would share.
 
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Discussion Starter · #6 ·
Rich: The TTS transfers power

Rich: The TTS transfers power to the inner coil of the start valve relay (#86). Continuity to ground verifies this transfer. This activates the start valve relay to send power to the CSI.

I cannot see how continuity to ground does NOT transfer this power, unless the relay or air flow switch is temporarily stuck, thus causing no signal to the CSI. The TTS can NOT be "stuck", and show continuity at the same time. Continuity means that electrons ARE flowing.....they must.

This is my understanding as I study the wiring diagrams, and use basic concepts of electrical flow.
 
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Discussion Starter · #7 ·
Yes, it can. A TTS that is wo

Yes, it can. A TTS that is working properly will show continuity warm and cold by itself out of the vehicle.
If you don't like my tips don't use them but I have had a TTS show cont. when cold out of car and no cont. when warm out of car and guess what, it wouldn't spray the CSI. A good TTS from a 308 will show cont. when cold and warm due to the heat winding touching. Hence, why they tell you to test 12V to battery with W or put a test light on the TTS during cranking. Also TTS don't just stop when cranking stops like some manuals will have you believe. The 308s circuit is slightly different. Power flows through a protection diode then through the TTS to the CSI.

Anyway, think what you want but you are misleading people and I have spent many hours with TTSs and CSIs especially on this particular problem.
Anyway, sorry to waste your time with useful tips. I won't make that mistake again since you seen to think you know everything about TTS and CSI. I shouldn't have wasted good tips and let you chase another problem for a year like your last one.
 
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Discussion Starter · #8 ·
Rich: Thank you for the tip.

Rich: Thank you for the tip. I didn't mean to start an argument....SORRY!!! It appears that it will take me a year to really understand this.

Thanks again.
 
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Discussion Starter · #9 ·
Ok, no problem. I just wanted

Ok, no problem. I just wanted to share what took many lots of time to diagnose and solve. Thought it might help out someone.
 
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