12h-t won’t turn off (1 Viewer)

[ibinazbass]

First off, I have very limited knowledge of the 12ht itself. However, I have worked on mechanical injection Cummins before. Wiring systems are my jam though!

First test, turn the key off and remove the engine relay. Does it click when you remove it? If not, try removing it with the key on. Does it click now? If it does not click during either, it's likely shorted internally.

If it clicks while the key is off test the female terminals beneath the relay. Most relays have a diagram on them. Does yours? Post it if possible.

 

[kevin in okinawa]

First off, I have very limited knowledge of the 12ht itself. However, I have worked on mechanical injection Cummins before. Wiring systems are my jam though!

First test, turn the key off and remove the engine relay. Does it click when you remove it? If not, try removing it with the key on. Does it click now? If it does not click during either, it's likely shorted internally.

If it clicks while the key is off test the female terminals beneath the relay. Most relays have a diagram on them. Does yours? Post it if possible.

GREAT NEWS! It operates in standard fashion once again! I can’t hear s**t so I enlisted my eagle-earred wife and we had something clicking away, (in the general firewall/behind it direction or area) clicking as I made contact with the Engine fuse.

I tried also hearing anything from the 02005 relay, but it was unobserved. I did plug/unplug the relay at least 4-5 times.

It has gone back to being as dependable as ever. Perhaps the ignition relay is “going bad?” I have a new one coming from Amayama ( ordered just before Japan shuts down for new year’s) , finally a part under $20! Score!

I will wait until it happens again then swap it out with the new relay to test theory.

Super stoked that I figured out an electrical issue. Thanks to EVERYONE that replied and shared your insight and know-how. I always try to pay it forward on here, it helps.

 

[cruiserpilot]

yes I do, and one of those things that light up/probe also, lol. What can I test?

My kind of electrician! J

 

[ToyotaMatt]

GREAT NEWS! It operates in standard fashion once again! I can’t hear s**t so I enlisted my eagle-earred wife and we had something clicking away, (in the general firewall/behind it direction or area) clicking as I made contact with the Engine fuse.

I tried also hearing anything from the 02005 relay, but it was unobserved. I did plug/unplug the relay at least 4-5 times.

It has gone back to being as dependable as ever. Perhaps the ignition relay is “going bad?” I have a new one coming from Amayama ( ordered just before Japan shuts down for new year’s) , finally a part under $20! Score!

I will wait until it happens again then swap it out with the new relay to test theory.

Super stoked that I figured out an electrical issue. Thanks to EVERYONE that replied and shared your insight and know-how. I always try to pay it forward on here, it helps.

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Kevin ,

i can have the 90987-01004 24V relay in stock if that helps ?