Another starter failure

[Dimebag]

Seems like the relay stuck on and i fried my starter. There was smoke coming from the + terminal on the battery.

I now measure a direct short between the starter positive lead and ground. Can anyone verify how many ohms Im supposed to measure there?

Question is, even with the relay gone.. why do i get code 12 (crankshaft position sensor) and code 46 (ecu voltage) in the display?

All fuses are ok, and fuel pump goes like it should.

Where do i start? (Except ordering a new starter and relay)..

I have tried to replace the battery, but still get the same fault codes. And no luck jumping the starter relay either.. So its probably shot.

Thanks

 

[Rockmeister]

A new thread? lol

I posted a bunch of info on this here: http://www.ty4stroke.com/viewtopic.php?t=118072

As far as your codes, there is a good chance that most will clear once you start your sled.

Your stator has a good chance of being cooked also.
You can test the starter with a 12v battery and jumper cables, however, it IS most likely a dead short.
Just do a quick touch of the final connection, a short will throw a BUNCH of sparks, a good starter will spin and throw some sparks when connected.
(You will definitely know if it is a dead short.)

Once you replace everything, make sure you KNOW you fixed the cause so you don't have to replace it all again in a week!

Rock

 

[Dimebag]

Yep, its a dead short. And there definately was no cranking when i shorted out the relay..

The relay is stuck in the ON position, so I guess thats the reason the starter failed? Dont you think?

I have a new starter on the way already..

This happened on my backup sled… On my turbo sled i have the starter saver… guess I should have had one on this one too….

 

[Rockmeister]

The relay could have stuck due to a failed key switch also, would replace it too.
The relay will usually weld itself closed when the switch sticks.

 

[yamanytro121]

Yea i CPS error when my starter failed also. i think you get that once your ecu reaizes your starter should be turning and the engine is not turning.

 

[Dimebag]

Thanks for the info guys.

I ordered a new starter last night. And I will change the key switch as well. Plus check all relays and the stator.

I am surprised the battery held up being shorted out completely for several minutes..

I will run a battery test on it before i install it again, but at least it took charge and reads normal voltage.

 

[Dimebag]

Can anyone tell me the purpose of diode "11" in the circuit diagram.
Part number: 4WA-81980-00-00 Diode, Assy.

Is it to protect the ecu for possible overvoltage?

How do i measure it? It does not respond to a regular diode tester.

The stator values was good. And Im gonna test the rectifier at work tomorrow with a 3-phase variac.

 

[Rockmeister]

It is a Transient Voltage Suppressor Diode.
It protects the ECU against the Inductive Voltage Kickback from the starter relay when the Magnetic field collapses.

Test by applying a Current Limited voltage across it.
Do not know the exact specs, but should be 18-25V or so for turn-on.
One direction will be open no matter what. (Until you kill it anyway.)
The other direction will turn-on with enough voltage supplied.

 

[Dimebag]

Thanks Rock!

I will test both the relay and rectifier at work tomorrow. Hopefully they will turn out good.

 

[Dimebag]

The diode opened at 20 volts.

The rectifier also seems to work. 14.8 VDC output with no consumers.

 

[Rockmeister]

Awesome!

For everyone else reading this, By "opened", He means it let current through it.

Rock : )

 

[Dimebag]

Swapped the starter and ignition switch yesterday. Codes went away and everything seems fine.

I found I had to loosen the subframe and lift it a little to be able to bend the engine far enough to get the starter out. Definately a two man job.

I will install battery quick connectors on my sleds, so i have the possibility to disconnect the battery if the starter should hang on in the future.

 

[fxnytro1050]

if you look at the front of the nytro engine it had a perfect place to put a small shackle through. I used that and an overhead jib crane for tilting my enigine but im sure you could use another sort of method to tilt it for a one man job

 

[Dimebag]

Yep, thought about it, but already used the jib crane to lift the front up in the air. It was a much easier job than expected