2007 scion tc viper 5901 ignition relay

Hi, i have a question about hooking up Viper 5901 to Scion TC 07. Yes, I've searched the forum and wouldn't have asked if found the answer. I am clear on all other wires except H3 harness from Viper 5901. My question is: i have to use a relay to connect to ignition, but not sure which wires go to Viper 5901 H3 <-Relay-> Ignition. Here is the wiring scheme for ignition from the service manual: Here is the H3 Remote Start wiring harness: Please look at pic below, and correct it.

You need a relay! But not for the purpose you have demonstrated!  The relay is needed for your second starter, you already have two wires that can connect to your ignition circuit! The pink-ignition one and the pink/white- ignition two,  the second starter wire is where the relay comes in, use the small 5 pin harness I believe it's the violet wire that sends a negative trigger signal to drive a relay!

I'm not getting it, why are you using a relay to connect the ignition up to this car? You simply connect the pink H3/1 to blue at the ignition harnes, and pink/ white H3/7 to the yellow at the ign harness. Then you must supply 12volts to 3/2 3/8 and 3/9 from the red at the ign harness.Mike M2

Tech Manager

CS Dealer Services

TT beat me to it. Do NOT just connect the two starter wires together, use a relay for it like he says...Mike M2

Tech Manager

CS Dealer Services

Man i still got it wrong! Don't connect anything to 3/8....Mike M2

Tech Manager

CS Dealer Services

The pink-ignition one and the pink/white- ignition two. I understand that. So H3 doesn't need any relays? So why does the connection H3/2 refers to flex relay 87? H3/1 Pink <--> IG1 Yellow H3/7 Pink/White <--> IG2 Blue The violet wire you referring to, is it from RS-OUT harness? I am confused then, do i have to connect these two? ST2 <---> RS-OUT/3 I guess what i am after, is the clear picture which wire goes where. Thank you.

Ok. So this is what i do with H3 wires. Still dont know what to do with starter wire ST1(Green). Can you guys describe in detail - "use a relay for it like he says..." Thank you.

Mike M2 wrote: Man i still got it wrong! Don't connect anything to 3/8....

Sorry didnt see you post in time. So this is correct now, for H3?

You are correct now. You still need a second starter relay tho. The AUX harness you show above, violet wire, will drive the relay(86). 85 and 30 to 12volts, 87 to the second starter wire in the car.Mike M2

Tech Manager

CS Dealer Services

Mike very appreciated! If it's possible can you explain why i need to use a relay for a second starter? Hope this looks correct.