1974 fj 55 only runs in start! (2 Viewers)

[n2666s]

Our original 1974 FJ 55 was having headlight issues and was trouble shooting the fuses underneath the panel; after trouble shooting the fuses that all looked good started the pig up again but would only run in start; ; OK fusible link looks good and it runs if hot wired battery to + on coil or both sides ballast resistor has to be the ignition switch !; got a lovely original NOS ignition switch from ToyotaMatt............. Matt; a BIG thank you for all the help getting the switch to me at short notice ; installed it BUT but same issue; runs on start; runs if i hotwire battery to coil or battery to either side of ballast resistor and the fusible link "fuse" looks good; somewhere the current is cutting off when ignition switch turns to run any advice?: am scared to drive her out of where she sits with the battery hotwired to ballast resistor or coil; appreciate any advice on where to go next;
Lou

 

[LandCrusher'70]

Have you put a meter or a test light at the switch to verify power? That’s where I would start. Then test power at the coil and work from there.

 

[n2666s]

thanks for the advice ; there is power to the new switch; there is power at the coil in start but not in run; the fusible link was replaced in the past with an inline fuse that is good after testing BUT the power through the fusible link goes to the epower steering box directly; the wiring diagram got off ebay is suspect as has two blue/red wires coming from ignition where we know there is one black /red and one blue/red trying to figure out .... will get to it again after daylight

 

[Steamer]

it runs if hot wired battery to + on coil or both sides ballast resistor

Just to clarify. Did you jump battery to both sides of the resistor at the same time? Or each side of the resistor individually for two separate tests?

 

[n2666s]

Just to clarify. Did you jump battery to both sides of the resistor at the same time? Or each side of the resistor individually for two separate tests?

tested both sides of the ballast separately; first the coil and it ran hot wired w/o problems then each side of the ballast and ran well both times but when switch is on run position there is no power coming to ballast

 

[LandCrusher'70]

Are you certain you’re getting power at the switch in the run position?

 

[n2666s]

Are you certain you’re getting power at the switch in the run position?

no power in run BUT power to start, then when off start and back to run; no power runs fine if hotwire ballast so am pretty sure problem is upstream but where ? as all the fuses test OK and wiring diagram off ebay has some issues such as two blue reds coming from ignition and there is only one blue red wire both on the original switch and the NOS that ToyotaMatt kindly sent my way

 

[Steamer]

So when key is in the run position, there is no power at the ignition terminal on the switch?

 

[LandCrusher'70]

If you do not have power in the run position at the switch, something is wrong at the switch!

 

[n2666s]

Landcrusher; thank you again; ouch ; I thought the same but switch is NOS never been used in sealed package don't have the ability to check which one is the run terminal as the wiring diagram for 1974 fj 55 off ebay is inaccurate and the wire colors are off there is one terminal that has no power in run will get the wire color on the cold terminal in run BUT it might be the start terminal that is cold after starting ......on the switch and wiring diagram one black and red and another blue and red............then both are suddenly blue and red and which one is which and go where??

 

[LandCrusher'70]

These diagrams are straight out of my FJ55 manual. One is labeled “(NEW)”. I don’t know which one applies to your pig.

 

[LandCrusher'70]

The ‘Old’ does show position w/ original wire color.

 

[n2666s]

LC; thanks again big time ; think your wiring diagram is for an older pig when the ignition was on the dash and not on the steering column; but the colors are the same and it gives position on your wiring diagram; the IG goes to the black and yellow wire run? will check it again now that I have your wiring diagram; and the black and yellow goes to the starter solenoid wondering where the black and red goes to as on my ebay diagram both black and red + blue and red turn to blue and red hard to back trace

 

[LandCrusher'70]

What I see is this:
BW / ST powers the starter solenoid (Start)
LR / ACC power to accessories (ACC)
BR / AM is your power into the switch from the fuse panel (Power+)
BY / AG powers the coil (Run)

 

[n2666s]

back again; key in off position power to black and red wire

 

[n2666s]

key to acc position power to red and black and blue and red

 

[n2666s]

Key in run position; power to all terminals except black and white "st" also 12 volts to ballast in and 9 volts out to + side of coil

 

[n2666s]

somehow the power goes dead after starting when key position reverts to run but there is still power to coil! also headlights not coming on which is why was checking the fuses and truck would not start after checked fuses that seemed to all be intact

 

[peesalot]

Wait, if there is power to coil in run then I’m confused

 

[peesalot]

Fuses are good but did you verify that circuit is hot ? The fuse block is notorious for the tabs that hold fuse corroding , also check back of starter for loose / melted wires