Cadillac Owners Forum banner
  • Hey everyone! Enter your ride HERE to be a part of September's Ride of the Month Challenge!
1 - 15 of 15 Posts

·
Registered
1991 Sedan Deville 4.9l 80k miles
Joined
·
91 Posts
Discussion Starter · #1 ·
I have read post after post, video after video, and more article than you could imagine. My Devile went from running nEar perfect to a no start no nothing condition! Battery is an AMG thats less than a year old, headlights don't dim when you turn the key, doesn't mater what gear you've selected you get the same! Nothing! Tested my relays by the glove box and they test fine. Relay clicks like it should when you turn the key to run

After that I can tell you its between the relay and the neural safety switch. I have pose on the yellow wire near the column when the key is switched to run and off like its supposed to. I do not have power entering or leaving the neutral safety switch. Any idea other than follow my yellow wire to the relay then back to the neutral safety switch? Yes I've checked all guides resumed and maxi.

On maybe a unrelated note periodically I lose the display for the fuel center and get a code for loss comm. Please help. I'm going to loss my job
 

·
Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
Joined
·
22,088 Posts
I have read post after post, video after video, and more article than you could imagine. My Devile went from running nEar perfect to a no start no nothing condition! Battery is an AMG thats less than a year old, headlights don't dim when you turn the key, doesn't mater what gear you've selected you get the same! Nothing! Tested my relays by the glove box and they test fine. Relay clicks like it should when you turn the key to run

After that I can tell you its between the relay and the neural safety switch. I have pose on the yellow wire near the column when the key is switched to run and off like its supposed to. I do not have power entering or leaving the neutral safety switch. Any idea other than follow my yellow wire to the relay then back to the neutral safety switch? Yes I've checked all guides resumed and maxi.

On maybe a unrelated note periodically I lose the display for the fuel center and get a code for loss comm. Please help. I'm going to loss my job
========================
FIRST - check for codes -

so - what systems/components affect the starter -

the SECURITY system -
resistor chip in the key -
the chip reader in the lock cylinder -

lock cylinder itself -

ignition switch -

neutral safety switch -

starter relay -

starter solenoid -

starter

main POSITIVE cable at the starter -

GROUND -

all the wiring between these components -

---------------------------

my GUESS would be the ignition switch
 

·
Registered
1991 Sedan Deville 4.9l 80k miles
Joined
·
91 Posts
Discussion Starter · #3 ·
========================
FIRST - check for codes -

so - what systems/components affect the starter -

the SECURITY system -
resistor chip in the key -
the chip reader in the lock cylinder -

lock cylinder itself -

ignition switch -

neutral safety switch -

starter relay -

starter solenoid -

starter

main POSITIVE cable at the starter -

GROUND -

all the wiring between these components -

---------------------------

my GUESS would be the ignition switch
With a trouble light I was able to test and positively confirm 12.3v when the key is turn to run if that's the last position. Or the one you expect it to turn over.

Update:
I installed a new starter but same result as I expected. But, I can give the purple wire that leaves the neutral safety switch and goes to the s terminal on the starter. With the key turned on it turns over and starts. Still no power going into the neutral safety switch. I hear the relay click while turning the key to run and have switched them around as well as bench tested them all to verify they work. I do NOT know if its sending voltage as I cant find the wire. I thought maybe it was disconnected there behind the panel of relays is there anything fuse or other between the relay and neutral safety switch?
 

·
2001 Deville
04 Deville
Joined
·
257 Posts
The neutral switch may not have power to it, it may just complete the ground circuit to the relay. if you jump the terminals at the relay does it turn over? if not the problem is in the wiring between the relay and the purple wire. if it does you will probably need a wiring diagram to determine the wiring to the relay. it may be a bad ground in the neutral switch circuit
 

·
Registered
1991 Sedan Deville 4.9l 80k miles
Joined
·
91 Posts
Discussion Starter · #5 ·
I can here the relay click over when I attempt to start. Do I need to still jump the relay to test? What ground or where is the ground I need to test?
 

·
Registered
'93 SedanDeville 60 Special
Joined
·
1,165 Posts
Have you tried to start when putting shifter to neutral ?
When you go to a forward gear, does the electric door lock work and when going to neutral or park unlock ?
Did you check for any error codes and if any what were they ?

I have a 1993 sedan Deville FWD 4.L engine and had a no start issue
In short, it was the start/neutral switch was out of alignment and the shifter on top of it was too gunked up
I cleaned that whole area up, lubed the shift area and did the alignment as I show below and that cured the no start issue
It is also common for this switch to go bad and have to be replaced.

Also, when problem of no start the electric lock/unlock would randomly work or not, but after switch was re-aliened
the auto lock/unlock works

Font Parallel Elbow Illustration Document

Automotive tire Motor vehicle Hood Bumper Font
 

·
Registered
1991 Sedan Deville 4.9l 80k miles
Joined
·
91 Posts
Discussion Starter · #7 ·
Have you tried to start when putting shifter to neutral ?
When you go to a forward gear, does the electric door lock work and when going to neutral or park unlock ?
Did you check for any error codes and if any what were they ?

I have a 1993 sedan Deville FWD 4.L engine and had a no start issue
In short, it was the start/neutral switch was out of alignment and the shifter on top of it was too gunked up
I cleaned that whole area up, lubed the shift area and did the alignment as I show below and that cured the no start issue
It is also common for this switch to go bad and have to be replaced.

Also, when problem of no start the electric lock/unlock would randomly work or not, but after switch was re-aliened
the auto lock/unlock works

View attachment 621646
View attachment 621645
It shows codes e52, e58, e91 then
, ee91, and f31
 

·
2001 Deville
04 Deville
Joined
·
257 Posts
code definitions PLEASE!! you are not testing the relay you want to test the wiring from the relay to the starter so find the positive terminal where the relay plugs in and looking at the schematic on the side of the relay determine which terminal the relay completes the circuit to the starter and jump those 2 terminals and see if the starter kicks it over. if it does that circuit is ok and your problem lies on the primary side of the relay if not its between the relay and the starter(secondary side) A wiring diagram will be VERY helpful in determining where the problem lies
 

·
Registered
'93 SedanDeville 60 Special
Joined
·
1,165 Posts
ZR1 aren't the auto door locks a programable feature so they may not be programed the same way? I don't know for sure on the early models
I do not find anything in my 1993 sedan Deville 60 special manual as to programming auto lock function
Nor in 22 years of owning it even with no battery connected for a day with this function changing
 

·
Registered
'93 SedanDeville 60 Special
Joined
·
1,165 Posts
It shows codes e52, e58, e91 then
, ee91, and f31
Codes make no sense as to the problem you're having
except if the
E58 code Vehicle anti-theft system ( VATS ) – Circuit faulty is correct
that would prevent starting.
Does the security light flash when drivers door is open ?
Clear codes and see if they all return


Here is wiring for park/neutral switch, fuse 19 in IPC fuse block
This service manual is for 1992-93 Deville, so not sure if same for 1991

Product Schematic Font Parallel Engineering
 

·
Registered
1992 Sedan Deville
Joined
·
37 Posts
My 92 had an intermittent no crank no start. Turns out there was an issue between the ignition and VATS module. I took a spare key, and soldered a couple wires to it and spliced it into the wire that goes from the ignition to the module. Haven't had an issue since. It's been about 5yrs.
 

·
Administrator
2002 F55 STS, 2014 Explorer XLT, F-150s
Joined
·
78,017 Posts
In Posts 1 and 3 he states that he's running an AGM battery that shows 12.3 volts at Key: ON.

His charging system is not set up to correctly maintain an AGM battery and 12.3 volts is not correct for what his fully charged (lead-acid) battery should show - 12.6.

Rectangle Font Parallel Number Symmetry


Food for thought ........... alternator/regulator charging protocols are different for lead-acid, deep cycle, AGM, and gel batteries. In some vehicles an incompatible battery causes problems.
 

·
Registered
1991 Sedan Deville 4.9l 80k miles
Joined
·
91 Posts
Discussion Starter · #15 · (Edited)
I decided to go back to the relay. Passenger side behind the glove box. They are in rows of 2 I seemed to have 6. My research shows that the left row second from the bottom is supposed to be the starter relay. I measure 12.2v when I turn the key to on. BTW I have pulled the relay from its socket for these tests. I first notice I cannot visually see any metal connection of any kind which should be pin 87. I also don't read voltage on any other pin when I turn the key all the way to run. I should see the 12v on 85 or 86 to activate the circuit while the key is turned all the way correct? Has anyone removed this junction box to see behind if?

Further more discovery lead to me removing all fuses and relays in (what is the name of TBE fuse / relay block behind the glove box on the passenger side?) And removing the 2 torx screws. I was able to pop the back cover from it. Now I can see the wires going in and where there connected. There is NOT a wire connection in the above mentioned spot. Odd thing is I can't see an extra unconnected wire. There is next to no slack to get a descent view. There has to be something in the hole were the 87 pin on the relay goes right?

Is there a wiring diagram for this block?
 
1 - 15 of 15 Posts
Top