1990 DeVille starting problems

[JeftyJ]

My problem started a couple of months ago. The car wouldn't start and my wife called AAA and when they arrived, it started. No jump, no nothing, he just turned the key and it started. (He, without checking anything told my wife, “…you have a bad starter, better get it replaced”!) A couple of weeks later it wouldn't start and I drove to my wife's location. When I arrived I turned the key and the car started. Since that time, there were many occasions that the car wouldn't start and we would wait 10 minutes and it starts. As it was an intermittent ‘electrical’ problem, I have been reluctant to take it to a shop and spend big bucks and not have the problem resolved.
A week ago the dash readouts went crazy, the lights went out, came on went out, gave crazy readings and drove my wife nuts. I broke down and took the car to a reputable shop and the guy spent hours trying to find the problem. He finally said, “…it probably has something to do with the aftermarket alarm system and I’ll need another couple of hours ($196) to remove the alarm system and then we can diagnose the problem”. I had him to wrap-up the car and I brought it home.
When I got it home, I did what I should have done before taking it to the shop, I checked the error codes. I found that I had an E47 (BCM-ECM data probIem) and a F32 (BCM-PCM data problem).
I found a post, on this site, and the guy indicated that he had the same problem as I and he resolved it by replacing the BCM. I replaced the BCM and the problems with the dash lights going crazy went away......but the car still, SOMETIMES won't start. When I turn the key, everything works except there is no power to the starter. When I wait for 10 minutes, it starts.
10 minutes rang a bell...the Retained Accessory Power circuit. The RAP allows the windows, radio, etc. to be operated after the key has been turned off----for approximately 10 minutes. So I checked out the fuses and relays in the RAP circuit and switched a couple of the relays. That didn't work. The car still will not start, SOMETIMES, when the key is turned---but it will always start 10 minutes later.
Again guys, IT AIN"T THE BATTERY and it isn't the ground strap. The battery is less than 6 mos. old and the ground strap(s) have been changed by Cadillac last year. It doesn’t appear to be the PASS key system in that we have three sets and the car fails to start with all three keys.
Anybody out there have any ideas?

[gscott73]

When my Pass Key system went kablooey, it didn't matter which of the three keys I had were used, the symptoms were always the same. Thats sure what it sounds like to me.

[deville555]

If it is in the ignition column that isn’t reading the key resisance for some reason, you can bypass it by putting some resistors in the wire that is for the key to be read in the ingnition column to equal the amount in your key to make the PCM think your key is in the ignition.

[gscott73]

Thats exactly how I cured mine. 98 cents at radio shack for the resistor and about a nickels worth of solder.

[dallasj]

but understand this i had the same problem with my 90 deville and when the key was the problem the security light was on and with that being the care it wouldnt start now with the light off it was fine so i replaced the lock cylinder, so if your security light isnt on i doubt that the key is your problem..

[JeftyJ]

DallasJ,

My problem was solved by soldering a resistor onto the two wires at the bottim of the steering column which bypasses the the lock cylinder. This is a far less expensive way than replacing the lock cylinder. Works for me .

JoeJ

[dallasj]

Originally Posted by JeftyJ

DallasJ,

My problem was solved by soldering a resistor onto the two wires at the bottim of the steering column which bypasses the the lock cylinder. This is a far less expensive way than replacing the lock cylinder. Works for me .

JoeJ

well thats good to hear jeff if it works who am i to argue happy to hear that your problem is solved..

[91 deville]

Which color wire(s) do you solder the resistor into and what size resistor? Having the same problem.

[JeftyJ]

You can find out the resister value with a VOM meter. If you don't have one, go to your local Radio Shack (or similar electronics) store and ask them to check the resistance for you. I don't have the car here now so I can't go and check the color of the wires. I believe that they are Orange of Yellow, not really sure. But if you search on this site, there are a number of posts relating to this problem and they give real good information on how to find and fix this problem. By the way, the resistor has fallen out of the key that I use and the car starts beautifully without a resistor being embedded in the key shank.

Joe

[Ranger]

Originally Posted by 91 deville

Which color wire(s) do you solder the resistor into and what size resistor? Having the same problem.

See post #44.
http://www.cadillacforums.com/forums...raining-3.html (91 deville battery draining)

[Chuwee]

I had the same issue on mine which drove me nuts and my dad took it to some shade mechanic that jumped the wire. Although this fixed the issue it is still not good but when I opened my column to try and figure out a turn signal issue I found that my key wire was cut...so I soldered the puppy together and have not had an issue. For all it is worth maybe these wire get cut with time and need to be fixed or replaced just my two cents.

[Ranger]

The wires tend to break from repeated use of the tilt.

[chubbyranger]

Quote from an e-mail I got from a Cadillac Tech that sold me my FSMs when my wires in the column broke:

A lot of the pass key systems not only disabled the starter but also stopped the electrical pulse to the injectors from the PCM. What normally happens is one of the two wires going into the ignition lock cylinder breaks. This is a common failure. To check this you will need an ohm meter, it doesn't have to be a good one, it can be a cheap ohm meter you can buy from radio shack for about 10 dollars if you do not own one. You will need to locate the two wires coming from the lock cylinder at the base of the steering column under the dash, use your service manual to help find these wires. They are in there own little harness just two little white wires. Unplug the connector and connect you ohm meter to the ignition cylinder side of the connector, put meter on 10,000 ohm setting ???. You should get some kind of reading when you insert your key into the ignition, the reading should remain constant while you rotate the key to the start position. If you get no reading or the circuit goes open when you rotate the key the wires are broken. If this is the case, you have 3 options, (1) hardest fix, purchase a new lock cylinder and disassemble the column and replace it. (2) easiest fix, Purchase a new lock cylinder, plug the lock cylinder harness into the car harness, put a spare ignition key into the lock cylinder and secure it up under the dash some where. Note: if you use this option and do not have a spare key, the key you use to start the car does not need to have a pellet in it, so you can go any where and have another key cut to use to start the car. (3) least expensive fix, Measure the resistance of the pellet in you ignition key with your ohm meter, go to radio shack and purchase some resistors of the same value and install them into pass key harness circuit, good luck.

[Chuwee]

Ranger do you think that soldering the wire is not a good idea and will break again? If so what would you recommend? Chubby although your options will work I think the best solution will be option 1 and I do not think it is the hardest. When I took my steering column apart it was not very hard and pretty much a simple process to put together. In the process I did discover other things wrong I was able to fix as well without removing the wires and having to plug back into the wiring harness. When I soldered the lock cylinder wires I did heat shrink the wires hoping that will give it some stability in breaking again but only time will tell. By the way chubby thanks for your help on my other issue and I finally got my baby back on the road for a little while. After I got it all put together I uncovered another problem where my rear brake cylinders are linking and to top it off both the rear ball joint and tie rob ends are bad as well. Autozone has all the part with lifetime for only $136 so I am happy about that...LOL

[Ranger]

Ranger do you think that soldering the wire is not a good idea and will break again?

That is as good of a fix as any. I would think it will out last the car. Look how long the original lasted.