Hey Folks, I'm back to working on my Tiger Cub I rebuilt last summer. I posted questions in September about rewiring because of PO rigged the wired and did away with all safety switches. I'm still trying to figure out how the safeties all work through the harness. Today's question is ...does Scag use a particular relay for the ignition ? I'm thinking the relay is not working as it should. I bought one from the local AutoZ and it doesn't send 12V on Green/White wire to the solenoid as diagrams show. Wires on the relay are correct according to diagrams. The PO cut into the Green wire, which is hot when switched to start, and ran wire to solenoid. Am I wrong thinking that the relay should switch from one terminal (86) through electromagnet to proper terminal (87) when 12V are applied ? AS you may can tell, I'm confused to say the least. Thanks for any suggestions ...
Scag Ignition Relay
- Thread starter Hayward51
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This is 2002 Tiger Cub STC 48A 20CV s# 7640064. I had to dig for the wiring diagrams I have. The manual diagram isn't much help.
Thanks for your reply. I have this diagram. Not the switch make/break table. All seems to be wired correctly with Green wire from switch to relay HOT when key to start. I don't understand how it gets to the Green/White (stripe) wire going to the engine harness. If I ground Green/Black (stripe) wire at the start, it connects to GreenWhite to engine. I'm assuming this happens through the safety interface module.?? Does this mean I have a bad module ?
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Not necessarily. Especially when someone has hacked the harness. The interlock module is controlled by the lay bar switches along brake, PTO, and seat switches.
Part of the problem is that interlock module is kinda of mystery box. Scag doesn't tell us how is configed inside. Apparently it need 12v to operate so there must be a relay type switch inside that grounds the green/black wire when safeties satisfies the circuit logic sequence. Personally I could rewire to a grounding logic setup removing the need for 12v to control the module but it would hard for to explain it remotely as I haven't done or needed to do the Scag interlock module bypass here just the JD ZTR ones. It is like doing heart bypass surgery you got to know what you doing at the time of the bypassing.
Just take your time an trace out the circuit making sure all the switches are working as intended.
Part of the problem is that interlock module is kinda of mystery box. Scag doesn't tell us how is configed inside. Apparently it need 12v to operate so there must be a relay type switch inside that grounds the green/black wire when safeties satisfies the circuit logic sequence. Personally I could rewire to a grounding logic setup removing the need for 12v to control the module but it would hard for to explain it remotely as I haven't done or needed to do the Scag interlock module bypass here just the JD ZTR ones. It is like doing heart bypass surgery you got to know what you doing at the time of the bypassing.
Just take your time an trace out the circuit making sure all the switches are working as intended.
I have verified that all safety switches are good. Looking at the diagram for a 5 pole relay, it shows that the terminal the green/black wire attached to is (or should be) grounded. I have the relay grounded. All this is very confusing to me but I would like to get the safety features working.
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Currently according the schematic Scag is using (feeding) 12v through safety switches and the interlock then converts this to a grounding circuit for the starter relay. In order to delete the interlock module the system would need to be converted to a grounding system.
This requires removing the red jumper wire from pole C to pole A on the PTO. Now disconnect the lt blue wire from the other pole C terminal and attach a ground to the terminal. Now at the interlock module disconnect the Orange, and the Green/Black wires. Tie those two wires together. The only left is get the seat to kill ignition if you are off the seat. This would require disconnecting the Brown and White wires from the interlock module and tying them together. Note don't do this unless the circuit is converted to a grounding or you will fry your ignition coils but only if the brake switch is activated. But I would prefer the seat to kill the engine anytime you are not on the seat so I remove the red wire at the seat switch and attach a ground to the ground terminal. This way whenever the operator is not present the mower will not run. (just in case operator get knock off the seat when mowing). And yes I had one customer that had someone to mis-wired his mower, it did happen, and the mower took out his wife's new car. Let's there was someone hunting him.
Quite easy to do when you know what you are doing but can be confusing to those that don't. So please don't try this unless are 100% sure know what you are doing.
This requires removing the red jumper wire from pole C to pole A on the PTO. Now disconnect the lt blue wire from the other pole C terminal and attach a ground to the terminal. Now at the interlock module disconnect the Orange, and the Green/Black wires. Tie those two wires together. The only left is get the seat to kill ignition if you are off the seat. This would require disconnecting the Brown and White wires from the interlock module and tying them together. Note don't do this unless the circuit is converted to a grounding or you will fry your ignition coils but only if the brake switch is activated. But I would prefer the seat to kill the engine anytime you are not on the seat so I remove the red wire at the seat switch and attach a ground to the ground terminal. This way whenever the operator is not present the mower will not run. (just in case operator get knock off the seat when mowing). And yes I had one customer that had someone to mis-wired his mower, it did happen, and the mower took out his wife's new car. Let's there was someone hunting him.
Quite easy to do when you know what you are doing but can be confusing to those that don't. So please don't try this unless are 100% sure know what you are doing.
Thank you for those instructions. I will study the wiring to familiarize myself thoroughly before snipping. BTW, the PO also removed the seat switch and connected the wires together. I'll have to replace the switch and plug.