Jared Richey Posted July 21, 2016 Share Posted July 21, 2016 Has anyone ever converted their warning light harness? Either by using the kit sonnie24 sells on ebay or on their own? I would like to modify my original harness because I have trouble with the one I bought that was already converted in my car... I'm trying to see if Sunny24 will sell just the wiring to do it without having to buy the whole conversion kit, otherwise I'm going to have to order another harness, to get my car going. I actually have a 72 kit from sonnie24 I ended up with but he said those wires will not work in a 70 harness, and of course the instructions are for 72 as well. I'm just trying to weigh my options to get my car going as soon as possible. Quote Link to comment Share on other sites More sharing options...
Rock Posted July 21, 2016 Share Posted July 21, 2016 My car had idiot lights and all I had to do is add 2 wires and change positions of some of the wires. I don't remember the exact moves but it was fairly simple. I did get the kit from Sonnie 24. His directions are real generic but are pretty straight forward. Quote Link to comment Share on other sites More sharing options...
RealRed70 Posted July 21, 2016 Share Posted July 21, 2016 I am not sure at what stage your present DASH harness is in. If these changes have not been made, you will need to add a brown wire to your dash harness 12 pin connector. This brown wire will be for the tach. It connects to the negative terminal on your coil. There is a small divot one inch lower and to the right of the throttle cable. This is where you drill a hole for the brown tach wire that goes to the coil. This wire will need to go through the fire wall with a grommet. You will need to plug the brown wire into location # 9 in the dash cluster 12 pin connector/ cluster plug. Then you will need a black wire and plug it into location # 4 of the cluster plug. The other end will need to plug into location D-S of the fuse block. Then you need a black wire with a white stripe and plug it into location # 3 in the cluster plug. The other end will need to plug into location D-T of the fuse block. The two black wires are for your amp gauge. You must move some wires around in the dash plug. #'s 1,2,8, and 12 remain where they are. You will need to move the light green wire to location # 5, the dark blue wire to location # 6, the pink wire to location # 7, the dark green wire to location # 10 and the tan wire to location # 11. Then take the remaining brown wire and remove it from location C-U at the fuse block. If there is a small brown wire with a red stripe, leave it connected and just clip the end off the large brown wire. Now you need to convert the forward lamp wiring harness. You will have to add a black wire with a fusible link on it to location D-S of the lamp harness connector. Attach the other end to the junction block on the radiator core support behind the battery. Now you will need to add a black wire with a white stripe and a fusible link on the end to location D-T of the forward lamp connector. Connect the other end to one of the positive screws on the horn relay. Now for your temp gauge you are going to have to change your temp sending unit to a full gauge style. This sending unit is installed in your head on the drivers side. The connector that plugs onto the new sending unit is different than what was used with idiot lights, and will have to be changed by clipping it off and installing the correct style for gauges. The sending unit wire is a dark green wire. You will need get some of the special pin terminals that plug into the 12 pin cluster plug to add to the ends of the black, black with white stripe and brown wire. You will also need the terminals that plug into the fuse block and lamp harness. I sell the 12 pin connectors and pins as a kit. Are you confused yet. Good luck. It really is not that bad. Quote Link to comment Share on other sites More sharing options...
MCfan Posted July 21, 2016 Share Posted July 21, 2016 Jared, I can send you more detailed instructions with diagrams for the Sonnie24 gauge conversion for a '70 if you send me your email address. Like Rock already said, that conversion kit simply adds two wires (but not to the harness) and relocates several wire connectors in the circuit panel and fuse panel plugs. If that's what you mean by "converting an idiot light harness", then, yes, several of us have done it successfully. If you are trying to end up with a "factory" looking harness for a full gauge dash, this conversion kit won't do that. Quote Link to comment Share on other sites More sharing options...
RealRed70 Posted July 21, 2016 Share Posted July 21, 2016 You have to add two wires that get taped up in the DASH harness, beside moving some wires in the plug. They are the two black wires that I described in my post above, You also have to run a brown wire to the tach through the firewall. This wire does not go to the fuse block at the firewall. It goes through the firewall at the location that I stated in my last post. Here is a picture of a 12 pin connector kit Quote Link to comment Share on other sites More sharing options...
Jared Richey Posted July 21, 2016 Author Share Posted July 21, 2016 Just to clarify my car already has tach and gauges and I did the conversion last year and installed and already converted tach harness, unfortunately I didn't make it home from the Eastern Meat and something has went bad wrong with my harness after intermediate trouble with it throughout the year, instead of paying 80 bucks an hour for someone to diagnose the problem and still not be able to fix it I would just rather change the harness and be done with it.... My email address is Jared1970MonteCarlo@yahoo.com Thanks for the replies so far, what I'm trying to do is use my original harness to get my car going again I could care less about it being completely original looking. Quote Link to comment Share on other sites More sharing options...
Jared Richey Posted July 21, 2016 Author Share Posted July 21, 2016 can you tell me what's the PURPOSE of adding this wire to the forward lamp harness? Because I didn't do that last year, only thing I changed was the temperature gauge stuff, I also got the converted amp gauge to oil pressure from TachMan, but that's beside the point.... could this mixing wire in the forward lamp harness be causing my crazy issues, stuff coming and going like signals, park lights, and power from the IGN terminal. It got so bad I had to hotwire the coil just to make it back to where I could. Quote Link to comment Share on other sites More sharing options...
RealRed70 Posted July 22, 2016 Share Posted July 22, 2016 Why do you think the problem is in the harness? Usually most dash wiring problems are caused by grounding issues, bad / damaged printed circuit boards or faulty headlight switches. The two wires that I referred to that need to be added to the forward lamp harness are for the Amp gauge, but you do not have one of those. I do not know how the printed circuit board is affected with your non original oil pressure gauge that you added. I only know how to make this work as GM intended. Quote Link to comment Share on other sites More sharing options...
Jared Richey Posted July 22, 2016 Author Share Posted July 22, 2016 You cut that area away for the oil pressure gauge. Something must be wrong in my fuse box. It was a converted harness from one of those people who convert and recondition original harnesses, and I don't think they got something right in the fuse box. Quote Link to comment Share on other sites More sharing options...
Jared Richey Posted July 29, 2016 Author Share Posted July 29, 2016 I got my car fixed I ordered another harness from the harness tweaker. Once I installed everything went back to working as it should, thanks for sending me the conversion instructions I know I will use them at a later date because I plan on trying to teach myself how to do it using the sonny kit. Quote Link to comment Share on other sites More sharing options...
RealRed70 Posted July 29, 2016 Share Posted July 29, 2016 Glad you were able to get it working correctly. Quote Link to comment Share on other sites More sharing options...
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