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2003 cat 307c glow plug problem???

Catman75 ยท 2012-10-18 21:34

Guys I just bought this exvavator and everything on it is in great working order the problem I do have is the glow plug light is staying on constantly checked for power at the glow plugs and have nothing any ideas on where to go with it?? Thanks Jason

Replies5
  1. #1Lee-online2012-10-18 22:11

    When you turn the key to heat, that energizes a relay that energizes the glow plugs and also turns on the lamp in the moniter panel. If it is staying on then the relay could be bad or you have a short in the wiring or key switch. The relay is in the fuse box panel. Not plugged in but hard wired under the access cover on the side. It should be the top one, part # 085-5353 (bottom it the start relay)

  2. #2Catman752012-10-19 22:30

    Thanks lee I will check that out and see what I find is there anyway to check the relay or just replace it??The s/n is BNE0038 or 83 can't remember now but it's one or the other thanks!!

  3. #3Catman752012-10-23 23:04

    Ok guys got an update on the glow plugs I replaced the relay and I don't think it was wired right someone had put a jumper on the relay from the middle post back to the top post the new one had a bronze colored plate connecting the two together so after checking voltage on the wires I discoverd I had two wires that are carrying 24 volts I have all 3 red wires on the top post no wires on the middle post and I have a yellow and a orange wire on the bottom post and a small purple wire on the post on the side of the relay.That being said I am still Not getting Power to the glow plugs even though the indication light I'm the monitor is cycling and goin off all though its only cycling like the rest off the system check lights it is not staying on for any extended period of time and its 48 degrees here tonight so I still have a problem just don't know wich way to go. And to add something the orange wire on the bottom post of the relay runs to what I would call a power strip were all the big wires screw Into and there it does attach to the strip with the big glow plug wire wich runs to the plugs and is supposed to provide the power to them but as u said I'm getting no powere even when the indication light cycles. Hope you guys can set me strait so I can get this issue lined out and by the way the s/n is Bne 00138 thanks for the help guys. Jason The All

  4. #4Lee-online2012-10-23 23:31

    You should have 3 red wires connected to a fuseible link and that is connected to one of the big posts on the relay, these are hot all the time from the battery. On the other big post there should be 2 yellow wires, the smaller goes to the dash light and the other to the glow plugs, only when the key is turned to heat. On the control terminal is the purple wire (goes to the key switch) and on the other is the black ground that is also a fuseible link. If the relay is working and you have voltage at the yellow at the relay when key is turned to heat but not at the glow plug then there is a break in the wire somewhere. First, disconect the yellow wire from the glow plug buss bar and then check it. The glow plugs may be shorted and drawing too much.

  5. #5Catman752012-10-24 19:15

    Lee I am only seeing one yellow wire and then I have a orange wire that goes down to a power strip of sorts and there it is tied in with the yellow wire that feeds the power to the glow plugs.And I am not seeing a black ground wire but I do have the purple wire that is hooked up to a small screw on the front side of the relay. And one more question if I may on wich stake on the relay should I have the wires all the red I have hooked together on the top stake,the middle stake has nothing,and the bottom stake has the small yellow wire and the orange Wire that feeds the power strip and is hooked together with the yellow wire to the glow plugs hopefully that ain't to confusing I can take some pictures if u need them thank you very much lee.