300 TDi Auto random no starter motor action...g

Hi loanrangie,
I did contemplate re-soldering the pin and putting it back, then I remembered the situations that this spot of solder had landed me in and where the spider actually is and how inaccessible it is, I decided that the bypass was the safest way out of this. Next time I might be in a bit more of a predicament where I do need to move the vehicle with a certain amount of urgency.
Just a choice thing I suppose, the general advice of others on this forum and others was to simply install the bypass. The vehicle is now rebuilt and performing faultlessly.
Getting the spider out and back in again is four hours of my life I will never get back. Thanks for the comments.

Hi Dave,
Well everything works a treat so something must be right, as for the two acronyms, haven't got a clue what they are, maybe you could enlighten me.
Right now I'm just happy to here the engine starting.........every time. Bonus.....

Marty

fair enough...

they are types of switch configurations. D means double S means single P means pole and T means throw so (M means momentary L means latching)

SPST is a single pole single throw switch the horn button is a good example of a momentary version of one of these switches. it makes or breaks an electrical connection on one wire.

SPDT means it controls one wire but it lets you pick which one of 2 other wires it connects to. An example of this is the gauge selector switch in a series landrover with a manual change over valve.

DPST is essentially the same as a SPST but it makes or breaks a connection on 2 wires at the same time.

DPDT means that you can control 2 wires at the same time and each of them will select between 2 connections.

other things to watch for are

Pull on (pull it and it makes the connection
pull off (pull it and it breaks the connection)
push on
push off
Center off (only related to Double pole switches and means that the switch has 3 positions on left, off and on right)
Spring on
Spring off (spring loaded switches)
NC (normally closed means it connects in this position and mainly relates to spring loaded switches, relays and latching switches)
NO (normally open means its not going to conduct in this position in normal conditions)

If you're going to buy a switch the best kind of switch to buy (if you're not sure what your going to need to do the job) get a double pole double throw center off switch.

good work, your next project will be the Window ECU, same thing dry joint, stops rear windows intermittantly working.

Hi There,
Windows fine, I can handle that, engine not running, ............nah. Just living the dream.............., do they have a bypass as well or is that just called a handle.....

Quote:

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Originally Posted by Nomad9

--you can see the failed soldered connection. The tip of the screw driver points to the failed connection. .

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To fix that unit, you need a soldering iron, solder, solder sucker, cleaning solvent, cotton buds and maybe a magnifying glass.
Heat the joint adding more solder, then heat again, quickly suck the added and old solder out of the joint, if necessary scrap and clean with solvent, the copper and the component leg.
Finish by re-soldering the joint with fresh solder to the correct shaped fillet.

Doing this for each joint in turn and then you are on the way to curing your problems.

Dry joints are basically caused, when the tin migrates out of the solder into the copper track or pad, leaving behind a coating of lead oxide between the copper and the rest of the old solder, the other cause can be insufficient time for heating when the unit was soldered originally in a wave flow solder bath, a close inspection of those joints, sometimes show up as a crazing effect in a ring around the leg of the component.
.