Guest Posted March 3, 2003 Share Posted March 3, 2003 Hi,My 1970 Cutlass has been determined to have its original transmission (see post below).Does anyone know if it should have a TCS switch or a reverse light switch? I ask because I have a wire leading down to the transmission, but cannot find where it should attach. The plug at the end has a female connector with two holes in a "T" formation, like what you'd see for TCS. I have scoured the Assembly Manual and the Chassis Service Manual without success.Thanks for any input you might have. Link to comment Share on other sites More sharing options...
Sgt Art Posted March 3, 2003 Share Posted March 3, 2003 If the back up lights come on and the trans shifts properly, I wouldn't worry about it. Link to comment Share on other sites More sharing options...
rocketraider Posted March 3, 2003 Share Posted March 3, 2003 In the CSM- look at page 6C-16 fig. 6C-19, and at page 6C-19 TCS vacuum and electrical schematic and you'll see the TCS wiring harness routing. There should be one dark green wire running to the top bar of the "T" plug. A Turbo 350 transmission has no electric downshift, and the backup light switch is inside the car. The TCS switch is on the RH side of the T350 transmission case, forward of the dipstick tube. The JL transmission was used many years and you may have a later one as all 1970 cars had TCS. Look on the servo cover and there should be numbers stamped into it along with the tranny code. A 1970 transmission will have 70 stamped into the servo cover. Link to comment Share on other sites More sharing options...
Guest Posted March 6, 2003 Share Posted March 6, 2003 Yes, I've looked at that CSM picture several times. There is no switch on the transmission. Is it possible it was removed when the transmission was serviced? I believe the transmission was removed once for that. It appears to have a bolt at the location specified. The wire comes down and matches up exactly with the photo, but there's nothing there to connect it to.Is this TCS switch still available? Or might anyone know the part number? Or a source for a used one if needed?BTW, my transmission is 70 JL 066 which would fit perfectly for an early MY70 car built in Sept 1969. Link to comment Share on other sites More sharing options...
rocketraider Posted March 7, 2003 Share Posted March 7, 2003 Entirely possible. Is the TCS stuff still on the top of the engine? The whole system may have been disabled as it wasn't held in very high regard in those days. But with the prices NOS or even decent working used TCS solenoids are going for...1974 parts book shows p/n 6462514 as SWITCH, trans oil pressure spark control (on trans case), 1970-72 TH 350. It sold for $2.16.Look at it this way- at least you don't have to fight the 442 crowd for the TH 375/400 switch, so you may find one priced reasonable. Link to comment Share on other sites More sharing options...
Guest Posted March 7, 2003 Share Posted March 7, 2003 Yes, everything is still on top of the engine. The car is quite original and untouched, with the one exception that the transmission has been out.Of course, they did a bad job sealing it (pan, dipstick tube, etc), and it leaks so it'll have to be done again... Link to comment Share on other sites More sharing options...
Guest Posted April 7, 2003 Share Posted April 7, 2003 Hi again,Since my original post, I found someone selling a 6462514 as above. The problem is that the original TCS connector at my trans shows the switch should have two male prongs oriented like a "T". The vendor actually checked two separate 6462514's, and each has only one prong. I also found other switches that eventually "replaced" this switch in the GM parts books, and the male prongs are at least two, but oriented in parallel.Any other thoughts? I'd even take a used switch if anyone ever had one.Patrick Link to comment Share on other sites More sharing options...
rocketraider Posted April 7, 2003 Share Posted April 7, 2003 P- how many wires are in the harness going to the switch? If only one wire (dark green as in earlier post) and it goes to the top of the T, I think the switches you've found will work fine.Good luck! Link to comment Share on other sites More sharing options...
Guest Posted April 9, 2003 Share Posted April 9, 2003 Glenn,Two wires. One is green/black, one is red/black. They termintate in a boot, and in that boot are two female terminals (that would mate with male spade terminals) in a "T" formation.Patrick Link to comment Share on other sites More sharing options...
rocketraider Posted April 9, 2003 Share Posted April 9, 2003 Patrick, the only thing I can come up with is that the car may have been built with a Turbo 400 wiring harness (they may have all been to save having two different harnesses). The THM 400 downshift wire is orange/black or red/black and downshift solenoid wiring appears to be part of the Turbo 400 TCS switch connector. Look at page 6C-19 in the CSM and it shows the connector.Looking closer at this thing, it appears the TCS pressure switch itself is inside the transmission and the T-plug is only a connector on the outside. Green wire connects to a terminal that has a black wire inside the trans going to the switch. The red/black would connect to the wire going to the 400 downshift solenoid inside the tranny.So based on that, I'll say you need more than just the TCS switch. You need the t-connector and internal transmission wiring to make this thing work per design, meaning you'll have to go into the transmission.You have to decide if it's worth all that to you to restore a system that was designed to reduce performance. It was probably removed when the transmission was redone. The internal stuff may still be there, just the connector got broken when they were tearing the unit down and rather than try to find one they plugged the mounting hole.Keep us posted. Link to comment Share on other sites More sharing options...
Guest Posted April 10, 2003 Share Posted April 10, 2003 Glenn,Interesting CSM page. That connector is exactly what I'm lookng at (but I didn't know the red was nonfunctional). And you're right, they may all have the wiring but not use it.I don't suppose anyone else out there who might read this has a 70, 71 or 72 with a THM 350 that they could check for me???Patrick Link to comment Share on other sites More sharing options...
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