Before I jack the car up and bang the starter solenoid with a hammer (worked on other cars) or clean the starter terminals I thought I ask you. Car has new battery,
Also before I pull the steering wheel and may replace the switch with new one (cheap on eBay). I turn the switch and hear the fuel pump come on , clock comes on
etc etc but no starter kicks in. Once I hit the steering column with block of wood and it started..that was fluke. The shop manual shows a rod moving over to start mode sending juice to the starter solenoid. With all those 4 relays in the fuse box ..any of those part of the starter circuit ? By the way is there a way I can by pass the switch
to start the car so I can get it out of my gravel floor tent garage into my house garage. Another brand of car I owned and it had steering column switch with problems.
I miss my 2 57 Caddy's and 61 (now in Saudi Arabia) with dash mounted ignition switches. Any feedback appreciated. Gene
P.S. Once in my attempts to start the gas tank fuel pump would not shut off with switch off, had to unhook battery, Only happened once.
Jump the solenoid terminals on the starter, big cable to s terminal if it cranks you should check for 12 v to the solenoid in the crank position.
Gene,
I would check the Neutral Safety Switch located on the lower steering column. If this prooves okay than the issue MIGHT be with the ignition switch, That wire rod goes from the lock to the switch and in the full clockwise position of the lock it is supposed to pull the ignition switch to the start position. Could be alignment of the ignition switvh or the switch could be bad or it could be the relay. Need to start at one end of the chain and work to the end.
Greg Surfas
There is so much wiring in that car; in order to properly service it, you should have at least the
1979 CADILLAC SERVICE MANUAL, Cat No. S-1640. Another VERY USEFUL book is 1979
ELDORADO ELECTRICAL TROUBLESHOOTING MANUAL.
For maintaining 70s EFI cars I recommend having the blue & white book: CADILLAC ELECTRONIC
FUEL INJECTION DIAGNOSIS Manual 1099984 / S-1453. Its usually available on EBay, i have some
extra copies. Get a paper book, not a CD. Bruce Roe, 79 ELDO owner
Thanks everybody...still working on it, Its not the solenoid so far, will check rod alignment and neutral switch. Will get back to the club when problem solved. Gene
Also check the starter brushes.
The key switch itself is on the right side of the column under the dash so its not that difficult to access. There is a similar but smaller one on the left which is the highbeam. Same general area on top is the neutral switch which in the Cads is a more common failure than the ignition. The addition of the vacuum controls for the parking brake seems to make them a little more fragile.
Starter isn't too bad to do on these. It bolts to the transmission with 3 bolts which is unique to this body style. The solenoid is more likely to have issues than the starter itself especially from sitting in damp conditions. Solenoid is common to many GMs and is easy to replace.
Trying to remember is this car one of the first that has a starter relay near the fuse box?
My book shows a single wire running from the ign switch to the starter
solenoid. The switch is only allowed mechanically to turn in P or N.
There are a couple fat single pin connectors in that big purple wire
which can fail, and a branch also goes to the ECU for fuel injection.
Bruce Roe
Its a mechanical interlock on the ignition switch itself? Rather than the usual GM electrical via the neutral switch? If so I have never had to work on one like that before. Sounds like a place to have something get sticky with age.
Quote from: TJ HoplandIts a mechanical interlock on the ignition switch itself?
Rather than the usual GM electrical via the neutral switch?
Correct. Bruce
UPDATE I did get the Eldorado's' started by bypassing the steering column ignition switch (basically hot wiring). The actuating rod does not move far enough to engage
the start contact. To get under dash safely doors should be wide open otherwise at my age I may get stuck there. Because of damp weather leave that job till spring. Keeping car stock I will improvise by using trunk release yellow button with in line fuse and wire to starter solenoid. To start Step 1. Turn column switch to run position then push yellow button and presto car starts. Three years ago when I bought the Biarritz I noticed the heater was disconnected. Rather go through time consuming job
I decided to use the AC evaporator. It worked well for chilly Canada. See pix. Even put on off on switch for summer driving. Thanks everybody for your suggestions. Love
Cadillacs. :) Gene
The switch assembly has slots in its mounting holes that are used for adjustment. If that doesn't do it then the only other thing I have seen is a problem with the little rack and pinion setup behind the key. They sell repair kits for the mechanism.
I checked 3 of my 77-79 cars and 2 of the wiring diagrams including the
79 Eldo; none of them used a starter inhibit switch on the steering column.
The key isn't allowed to turn except in P or N. However some other models
(Starfire) did have a switch, so its not universal then. Bruce Roe
I wonder if that inhibit mechanism is what is causing his to not move far enough? Seems most likely. Stiff grease? Makes me want to go dig out a manual and see if there is a detail on that mechanism.
The usual failure of the rack and pinion is the rack part cracks and breaks.