Wiring Harness

GettaRobo · 04-26-2010, 04:31 PM

Just had a (hopefully) quick question. So I had to throw the wiring harness from my manual 88 NA into my auto 88 NA since some idiot glued the injectors onto the car with the auto harness. From what I have seen, there are no connectors to plug into the auto tranny and I was wondering if the car will even run or if there will be an issue with the neutral start switch or something due to those connectors not being plugged in anymore. If it won't start, is there any way to temporarily bypass the issue until I can do a swap to a manual tranny? Thanks

MA70-3.0GT · 04-26-2010, 05:23 PM

IMO you'd find it easier for the moment cutting the injectors off the old loom leaving plenty length in the wires & fitting small spade terminals (or splicing to the loom, but I'd say leave the correct loom intact for now) so you can plug them into the connectors on the proper loom.

I can't honestly say what would do what without looking at diagrams for both but I'd suggest you'd have problems with starter circuit, gear position indicator & possibly ABS/cruise etc as well by using the wrong loom. For how easy it is to cut the wires out the old loom I'm surprised you went to the bother of swapping looms over really, are the plugs really well glued on too? Sometimes gentle persuasion with a small screwdriver can get shot of superglue (bet they were glued 'cause he snapped all the clips off removing them incorrectly one time & wasn't inventive enough to string a bungee over the tops to hold them on!)

Anyway stick with the proper loom & avoid the problems you'd cause yourself for the sake of some goon, use the spade connector method & when you get new injectors it's just plug'n'play.

GettaRobo · 04-26-2010, 07:54 PM

Yes, the connectors were on so well that the connectors ended up breaking off. A lot of the other connectors are really messed up to. Most of the clips are broken on it. Basically I'm thinking of doing a complete engine and tranny swap since the engine hasn't worked right off the get go and no one knows what's wrong with it. The starter is probably a valid point and that could turn things ugly... I guess maybe I'd be better off finding a new auto loom on ebay or on the forums.

P.S. The only reason I even went into the injectors was because they were giving funny ohm readings and that's when I found that the connectors were 'stuck on' to the injectors

GettaRobo · 04-28-2010, 05:58 PM

It seems to me that the main problem with using the manual loom with the auto tranny is the tranny itself since there is nothing for the connectors to plug into. If I were to use the manual loom and swap over the W58 from the parts car, would it be reasonable to assume that the issues mentioned above would go away?

Supra_Freak_7m · 04-28-2010, 06:22 PM

You would have new issues though. You have to do something to close the starter circuit so you can start the car. It is normally the auto neutral safety switch that allows the car to start in neutral or park only. I believe this switch is closed for on and open for off. However a manual neutral safety switch is open (meaning button is not being pressed )for on and closed for off similar to a stop light switch. Not 100% positive on that but I believe thats how they work.

GettaRobo · 04-28-2010, 07:05 PM

Yeah I was reading somewhere that you can jumper the connector for the neutral start switch which causes the reverse lights to magically not work anymore. It mentions that you have to wire them up separately for functionality, but I can't remember where I saw it.

04-26-2010, 04:31 PM	#1
GettaRobo 3" Exhaust Join Date: Apr 2009 Location: Saskatoon, SK Posts: 65	Wiring Harness Just had a (hopefully) quick question. So I had to throw the wiring harness from my manual 88 NA into my auto 88 NA since some idiot glued the injectors onto the car with the auto harness. From what I have seen, there are no connectors to plug into the auto tranny and I was wondering if the car will even run or if there will be an issue with the neutral start switch or something due to those connectors not being plugged in anymore. If it won't start, is there any way to temporarily bypass the issue until I can do a swap to a manual tranny? Thanks

04-26-2010, 05:23 PM	#2
MA70-3.0GT 12psi boost Join Date: Oct 2009 Location: Crewe, England Posts: 356	IMO you'd find it easier for the moment cutting the injectors off the old loom leaving plenty length in the wires & fitting small spade terminals (or splicing to the loom, but I'd say leave the correct loom intact for now) so you can plug them into the connectors on the proper loom. I can't honestly say what would do what without looking at diagrams for both but I'd suggest you'd have problems with starter circuit, gear position indicator & possibly ABS/cruise etc as well by using the wrong loom. For how easy it is to cut the wires out the old loom I'm surprised you went to the bother of swapping looms over really, are the plugs really well glued on too? Sometimes gentle persuasion with a small screwdriver can get shot of superglue (bet they were glued 'cause he snapped all the clips off removing them incorrectly one time & wasn't inventive enough to string a bungee over the tops to hold them on!) Anyway stick with the proper loom & avoid the problems you'd cause yourself for the sake of some goon, use the spade connector method & when you get new injectors it's just plug'n'play. __________________ '89 MA70 Supra GT aero 3.0turbo JDM, Rebuilt motor, K&N intake, 3" stainless turbo-back. New turbo and braided line kit... '89 Honda NC27 400, NC23 cams, open pipe, PC36a shock & possibly Showa USD forks... '83 Yamaha 29R XJ750E-II, number 69 off the line, only runner in the country? Original except Koni shocks '95 Honda PC26 CB500R, Winter hack, hateful, trying to sell it I'm not paranoid, they really ARE after me!!!

04-28-2010, 06:22 PM	#5
Supra_Freak_7m Intake Join Date: Apr 2010 Location: Montana Posts: 40	You would have new issues though. You have to do something to close the starter circuit so you can start the car. It is normally the auto neutral safety switch that allows the car to start in neutral or park only. I believe this switch is closed for on and open for off. However a manual neutral safety switch is open (meaning button is not being pressed )for on and closed for off similar to a stop light switch. Not 100% positive on that but I believe thats how they work. __________________ 1987 Toyota Supra 7MGTE AUTO 1987 Toyota Supra 7MGE MANUAL 1990 Toyota Supra 7MGTE AUTO-> MANUAL

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04-26-2010, 07:54 PM	#3
GettaRobo 3" Exhaust Join Date: Apr 2009 Location: Saskatoon, SK Posts: 65	Yes, the connectors were on so well that the connectors ended up breaking off. A lot of the other connectors are really messed up to. Most of the clips are broken on it. Basically I'm thinking of doing a complete engine and tranny swap since the engine hasn't worked right off the get go and no one knows what's wrong with it. The starter is probably a valid point and that could turn things ugly... I guess maybe I'd be better off finding a new auto loom on ebay or on the forums. P.S. The only reason I even went into the injectors was because they were giving funny ohm readings and that's when I found that the connectors were 'stuck on' to the injectors

04-28-2010, 05:58 PM	#4
GettaRobo 3" Exhaust Join Date: Apr 2009 Location: Saskatoon, SK Posts: 65	It seems to me that the main problem with using the manual loom with the auto tranny is the tranny itself since there is nothing for the connectors to plug into. If I were to use the manual loom and swap over the W58 from the parts car, would it be reasonable to assume that the issues mentioned above would go away?

04-28-2010, 07:05 PM	#6
GettaRobo 3" Exhaust Join Date: Apr 2009 Location: Saskatoon, SK Posts: 65	Yeah I was reading somewhere that you can jumper the connector for the neutral start switch which causes the reverse lights to magically not work anymore. It mentions that you have to wire them up separately for functionality, but I can't remember where I saw it.