Glow plug relay issue.....again

[CUCVLOVER]

I would either re do the whole thing so you know its right or convert back to stock.
Just my

 

[MarcusOReallyus]

If that Blue wire tap is new, I suspect it may be the culprit.

Agreed! Dirty, I used to install cellphones (back when they were CAR phones) and business radio equipment for a living, and I do NOT like those type of taps. I found them to be unreliable, as did my colleagues.

This is the kind I use. MUCH more reliable.


That aside, I'm beginning to wonder if all the problems were caused by the blue wire having a bad connection between the card and the relay.

 

[M1008driver]

It looks like from your pics your push button switch is the same as mine. I would say the problem is somewhere in the gp bypass or relay s603. Here is a pic of mine.

 

[Dirty1]

I updated post #9 with these pictures of what I am working with.


The picture of the installed relay is upside down. Oops!

I can not work on the truck today but hopefully on tomorrow. I will keep this updated. Thanks again for all of your help!

 

[doghead]

update?

 

[Dirty1]

Sorry about that. It has been a busy couple of weeks at work.

I just came came inside from working on it. I installed a new wire from my switch to the relay and disconnected the light blue wire from the relay. I then reconnected my batteries. One is new and the other I charged overnight. I turned on my ignition and hit my momentary switch for the glow plugs. I heard the relay clunk and then about a second later the entire dash shut off and the ignition switch is not working.

I checked the ignition fuse and it is not blown. Both batteries have 12+ volts when I tested them with my multimeter. At the relay there is only 9.5 volts on the top post and 0 on the other three. There is also 9.5 volts at the 12 volt block right above the relay.

I have no idea where to go from here. I can do a little more investigating but I am going on vacation next week.

 

[doghead]

Sounds like the fusible link supplying the 12v stud has failed.

 

[Dirty1]

Thanks I will check it out. I don't have a garage and it is supposed to rain tomorrow, so I may not be able to check on it until next Sunday.

Thank you once again for all the help. I will do more reading on the electrical system while I am away.

 

[MarcusOReallyus]

S At the relay there is only 9.5 volts on the top post and 0 on the other three. There is also 9.5 volts at the 12 volt block right above the relay.

Dirty, test that point with a test light, not a meter. I suspect the light will not light.

Why?

If doghead is right (and he probably is), your fusible link has failed but there is a bit of residue that is partially conducting electricity along that path. Thus, you are seeing the 9.5 volts with the meter. Meters have a very high input resistance - they don't load a circuit at all. (Well, not enough to matter in automotive work.) If there is a very high resistance (like a corroded connection or a burned fusible link) between the battery and where you are measuring, the meter will measure the voltage, even sometimes full voltage, but put a load on that circuit and that high resistance will drop that voltage like a rock, and your test light will not light.

That's why it's always good to have a test light AND a meter in your tool kit.


Try the test light and let us know what you get.

Also, I suggest you test the resistance of your glow plugs. If one is shorted, you'll blow that link in a heartbeat.

 

[Dirty1]

Excellent info! I will do this. Thanks again!

 

[Dirty1]

Here is an update as of today. I got another new battery on Monday, so I now have two new batteries. I also replaced all four of the battery connectors and cleaned up what I could. I found that I was blowing fuse number 7 (30amp headlight). I am not sure why at this time, I am using the LMC headlight harness. After changing these, I found that I had normal voltage through out my glow plug system. The relay was working with my new switch and wiring. It has been starting without issue since Monday.

A big thanks for all the input during my issue! It was a huge help!