got a takeuchi 240 grid heater comes on for split second then stops. anybody give me a hand figuring this out
Guessing it's the light in the cab? Don't know offhand with that model specifically, but usually grid heater or glow plug time is determined from the resistance seen from cold until it heats up. First check would be to disconnect the wire at the grid heater and ohm from the heater post to ground, if it shows as an open circuit, then the heater element is burned out.
light in cab doesn't work. when I ohm the grid heater at pos post it shows.8 which I believe is high. would that cause the supply wire to get 12v for 4 or 5 seconds and then nothing at 30 degree temp?
0.8ohms from post to ground (with wire disconnected)?
ya wire disconnected.
when I turn the key counter clockwise, that is the wait to start position correct?. my light in cab doesnt work. but with the POS. disconnected from heater I get 12v for like 4 seconds with key still turns. all my relays are clicking. there is a small gauge yellow wire that goes from ecm to relay and I believe that is the switched 12v. when I apply power with probe the heater will come on as long as I have power to that pin in heater relay plug with relay plugged in. not sure if any of that makes since. I'm not greatest with electrical. I'm a engine builder.
also I've changed the heater relay and the temp relay. both coolant sensors. and ecm.
0.8ohms should be fine, and like you said it heats up with 12vdc applied. Is this a new issue that just started, or a new machine to you? Asking because I just remembered working on one (different model) years ago that a customer bought new and complained that the GPs weren't working right over the winter. It turned out that was how Taki had their system designed, it only heated BELOW 32degF. This is in the TL8/10/12 manual: 1. Turn the ignition key to the ON position, and confirm that the glow lamp is lit. (The glow lamp stays lit while the coolant temperature is kept at 0°C (32°F) or lower.)