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**hatzie** · 07-28-2019, 09:39 PM

Less than that on the purple wire. Probably more like 1 Amp. It's energizing an electromagnet coil in the starter solenoid... basically a big ole high current relay.

If you're using the PCM controlled starter wiring from the LS donor it's probably of the order of 5-10 ma to the starter enable on the PCM and 150 ma to the relay in the fuse-relay centre. It may really only be slightly more than that for the Delco MT starter solenoid S terminal but I tend to pad stuff out the nearest amp for safety.
The only reason to use 18ga wire for the starter solenoid S terminal is vibration resistance. You could likely send the energize current over 24ga wire and not worry about it if you didn't have to worry about vibration and such.

07-28-2019, 09:39 PM	#6093
hatzie Moderator Join Date: Oct 2008 Location: Wentworth, NH Posts: 4,915	Re: Restoring Rusty Less than that on the purple wire. Probably more like 1 Amp. It's energizing an electromagnet coil in the starter solenoid... basically a big ole high current relay. If you're using the PCM controlled starter wiring from the LS donor it's probably of the order of 5-10 ma to the starter enable on the PCM and 150 ma to the relay in the fuse-relay centre. It may really only be slightly more than that for the Delco MT starter solenoid S terminal but I tend to pad stuff out the nearest amp for safety. The only reason to use 18ga wire for the starter solenoid S terminal is vibration resistance. You could likely send the energize current over 24ga wire and not worry about it if you didn't have to worry about vibration and such. __________________ 1959 M35A2 LDT465-1D SOLD 1967 Dodge W200 B383, NP420/NP201 SOLD 1969 Dodge Polara 500 B383, A833 SOLD 1972 Ford F250 FE390, NP435/NP205 SOLD 1976 Chevy K20, 6.5L, NV4500/NP208 SOLD 1986 M1008 CUCV SOLD 2000 GMC C2500, TD6.5L, NV4500 2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263 2009 Impala SS LS4 V8 RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials... 1973-1991 GM Light Truck Service, Unit/Overhaul, Wiring Manuals, Parts Books and Some 1968-1999 GM Service Training textbooks in PDF 1988-1998 GMT400 CK service manual project 1988-1993 GMT400 CK parts books. 1967-1972 GM Light, Medium, & Heavy Truck Service Manuals in PDF Please include at least the year and model in your threads. It'll be easier to answer your questions. And please let us know if and how your repairs were successful.