[bns001]

New member.

Have been reading your forum for months... first post, so I'll try to be completely
informative.

Okay... Auto specs...
1998 Cadillac SLS NorthStar

I just replaced the battery, took a long test drive -- turns, start-stops, hills.

Disclaimer -- Have always gotten the dreaded "suspension" message ,
"Speed limited to 90 MPH".
Dealer mechanic told me there must be a short in the sensor,
that suspension is fine.

When I got back, I compiled ALL of the DTCs in the ol' on-board 'puter...
11 codes...
took forever.

Yes, I read http://www.cadillacforums.com/forums/cadillac-seville-cadillac-eldorado-forum/138258-how-pull-codes-dtcs.html a long time ago.

Today's List of Codes --

• ABS C1255 HISTORY
• IPC B1652 HISTORY
• IPM B1340 CURRENT
• IPM B1344 HISTORY
• IPM B1652 HISTORY
• IRC U1016 HISTORY
• PCM P0603 HISTORY
• RIM B1328 HISTORY
• TTM U1300 HISTORY
• RSS C1711 CURRENT
• RSS C1738 CURRENT

Okay... I figure that the two RSS codes are related to the mystery sensor in the
suspension system sensor.

No, I'm not assuming, but I am used to the 90 degree speed limit.
I don't necessarily like the way the suspension system tugs to
wake me up if I'm lucky to be making good time... so ANY WAY to
disable that safety system (not the warning, but the jerking is just stupid.
If i'm already safe at 90 mph, than why should the car make driving hazardous?

The other "ABS C1255 HISTORY" code... I have that brake check scheduled, so
that message will go away after i replace the brake pads... I hope. If not, I'll
start a separate thread about how to disable that system/warning.

I will look into the other codes, but I wanted to post the entire list, and
get some feedback on the codes that I haven't seen or know nothing about.

Thank you, experts!

 

[Submariner409]

Re: SLS -- New Code list... need any advice on next steps...

The jerking is the car shutting down the fuel injectors. Either fix the problem or live with it. No way to bypass the faults.

What are the suspension and spring package codes on the RPO sticker under the spare tire cover ?? That will help in diagnosis. Your suspension appears to be monitored, so the car may - may - have an optional suspension system.

C 1711 - LF damper actuation circuit - is your problem. Sounds like a chafed strut pigtail or body harness fault. The C 1738 is why the car's tail is dragging - the ELC system is faulty.

Use this to decipher your codes, post it all here. (Bookmark the link - you're gonna need it again)

http://www.cadillacfaq.com/faq/answers/dtccode.html

 

[basscatt]

Re: 1998 SLS -- suspension codes... need any advice on next steps...

it is customary to include CODE DEFINITIONS along with the codes -

that way - anyone reading your post -
will have all the information at their fingertips -
without the need to stop and look up the code definitions -

Okay... I figure that the two RSS codes
are related to the mystery sensor
in the suspension system sensor.
actually - the C1711 - Left Front Damper Actuator Short Circuit to Ground code -
is the cause of the message and speed limiter -

ANY WAY to disable that safety system?
NO - the ONLY solution is to diagnose - and fix the problem -

The other "ABS C1255 HISTORY" code...
I have that brake check scheduled, so
that message will go away after i replace the brake pads... I hope.
C1255 has nothing to do with brake pads -

If not, I'll start a separate thread about
how to disable that system/warning.
once again - the solution is to diagnose - and fix the problem -
not disable something -

 

[bns001]

Re: 1998 SLS -- suspension codes... need any advice on next steps...

Thank you, basscatt.

First point to respond to, from my (a new poster) POV...

"customary" --

Actually, it may be "customary", but the "average" that I have seen over four months of
being led to these forums from Google searches is that there are more "how do I get rid
of this code?" posts (based only on the forum threads that I have been led to and study ).
So "customary" based on percentages might definitely NOT be "average".

Yet, being the "chatty cathy" that I am, I included my experiences with my car and
knowledge of the warning history of the car.

In my initial post, I did take the time to include the system code which spawned the DTC,
and whether the DTC was current or history... which I had NEVER seen in any other post
on any forum... yet always seemed to be requested in replies.

I am really unsure of whether I should have included the CURRENT records or not.
The way that CURRENT vs HISTORY was described initially, CURRENTs don't always
get to HISTORY unless they recur a number of times, and are thus validated as
being correct. That makes some sense, although I do not know if that is true on
the 1998 Cadillacs, or if that happened later.

RESPECTFULLY. ​

Next phrase to respond to, from an owner POV...

"stop and look up the code definitions"

Until 5 minutes ago, I had never seen a good list of codes with descriptions,
so all that I know of DTC/ODB codes is the codes.
I just happened upon http://www.cadillacfaq.com/faq/answers/dtccode.html ,
which was mentioned by submariner409 in his reply before I got back to the
forum.

YET, even these descriptions don't help me at my mechanical diagnostic level
all that much. The 3-letter SYSTEM code tells me which system spawned the
code, so my experience operating the car and my rudimentary knowledge of
what each system might warn about gives me an idea more quickly about
what the code is saying... more so than the description.

Not a mechanic. YET, I'm not afraid to research and use tools to perform any task
that I can. "Measure twice, cut once."

Problem-solving by diagnosing REAL PROBLEMS behind an amorphous CODE is
what I gave done for over three decades as a programmer.
​

While I may not have followed perfect protocol, I am still researching each code
in the report individually.
When I am finished, I will come back and detail everything correctly about what
I found. The code list was the most important part of the post to me, because it
gives me a way to PRINT the list instead of the small scratchpad which was all
that I had to write everything down on in the car, and methodically work through
it. Not the musings of a highly frustrated car owner part.

I appreciate the correction to my below-list comments.

Based upon initial research of the first codes that I looked at, one of them did
have something to do with the "check brake pads" message that I have been
seeing... Might not have been C1255. Sorry, but I was aware of that warning
from another message, so it was on my radar.

One of the codes has something about temperature regulation. (Maybe that
was why C1255 stuck hard in my memory while writing the opening post.)
I did check, and the driver side is blowing hotter air, so I will research more
on an "actuator" being stuck that I saw on another post.

Thank you again for helping, in any way that you can.

Peace.

 

[MoistCabbage]

I'll be honest, I didn't read all of that.

What it comes down to is, if you don't post code definitions, 99% of pople here aren't going to look them up for you. Very few members know a small handful of code definitions by heart.

Provided one of the more knowledgeable members are online, it's not uncommon for a post with definitions to be answered in minutes.

 

[Submariner409]

Re: 1998 SLS -- suspension codes... need any advice on next steps...

My POV: Subscribe the car to www.alldatadiy.com . It's the GM/Cadillac/Helm service manuals plus a LOT more: You're gonna need it.

You might also study the sticky posts and threads in any forum of interest - "Acronyms" is a good one to start with.

 

[bns001]

Re: 1998 SLS -- suspension codes... need any advice on next steps...

The other "ABS C1255 HISTORY" code...
I have that brake check scheduled, so
that message will go away after i replace the brake pads... I hope.
C1255 has nothing to do with brake pads -

Sorry. I thought ABS was reported from "brake system".

My confusion as non-Cadillac non-mechanic... just scientist.

 

[Submariner409]

Re: 1998 SLS -- suspension codes... need any advice on next steps...

C 1255 - EBCM internal malfunction is not good - usually signifies megabucks. It can be as simple as a corroded multipin electrical connector or as complicated as a full EBCM overhaul. Google www.modulemaster.com

 

[bns001]

ALMOST new member. Corrected previous post due to feedback,
and added new code descriptions from
http://www.cadillacfaq.com/faq/answers/dtccode.html ...
although little of it makes sense.

Okay... Here goes... 1998 SLS NorthStar (in profile now).

I just replaced the battery, took a long test drive --

• turns,
• start-stops,
• hills.

When I got back from test drive, I compiled ALL of the
DTC codes in the ol' on-board 'puter... 11 codes...
took forever, since I wanted a FULL report. It literally
took 9 passes through the report to get all of the data
without descriptions.
Then, I added the code descriptions.

Disclaimer -- Car has always reported the dreaded
"service suspension" message , as well as
"Speed limited to 90 MPH".
Dealer mechanic told me there must be a short in the
sensor, that the suspension is fine.

The biggest current problem that I think I know how
to express... she runs very week with rapid-fire
backfiring until in higher gears.

Yesterday's List of Codes w/ descriptions now --

• ABS C1255 HISTORY -- EBCM Internal Malfunction
• IPC B1652 HISTORY -- Loss of Keep Alive Memory (KAM)
• IPM B1340 CURRENT -- Air Mix Door One Movement Fault
• IPM B1344 HISTORY -- HeaterDefrost/AC Door Movement Fault
• IPM B1652 HISTORY -- Loss of Keep Alive Memory (KAM)
• IRC U1016 HISTORY -- Loss of Class 2 Communication with VCM
• PCM P0603 HISTORY -- Control Module Long Term Memory Reset
• RIM B1328 HISTORY -- Vehicle system voltage is greater than 15.9 volts
• TTM U1300 HISTORY -- Class 2 Short to Ground
• RSS C1711 CURRENT -- Left Front Damper Actuator Short Circuit to Ground
• RSS C1738 CURRENT -- Exhaust Solenoid Valve Short to GND

New battery explains --

• IPC B1652 HISTORY -- New battery (and previous battery swaps)
• IPM B1652 HISTORY -- New battery (and previous battery swaps)

Testing between posts --

• IPM B1340 CURRENT -- verified. Driver side blowing warm air.
• IPM B1344 HISTORY -- probably related

I don't necessarily like the way the suspension system tugs to
"wake me up" if I'm lucky to be making good time and able to
drive at 90 MPH... so ANY WAY to disable/fix that safety system,
but the jerking is just stupid. If I'm already safe at 90 mph, than
why should the car make driving hazardous?

Previous thread had this comment about the suspension-90mph
problem. researching...
from Submariner409 --
---
What are the suspension and spring package codes on the RPO sticker
under the spare tire cover ??
That will help in diagnosis. Your suspension appears to be monitored,
so the car may - may - have an optional suspension system.

C 1711 - LF damper actuation circuit - is your problem. Sounds like a
chafed strut pigtail or body harness fault.
The C 1738 is why the car's tail is dragging - the ELC system is faulty.
---
I tried to find an RPO sticker.
There was a "SERVICE PARTS IDENTIFICATION" sticker.
There was a VIN? followed by 6KS69 or 6K569.
There was a whole slew of random 3-alphanum codes.
The last line said BC/CC U141D 773.

I did not know that the tail was dragging. looking into that one.

I will look into the other codes, but I wanted to post the entire list of codes, and
get some feedback on the codes that I haven't seen or know nothing about.

Thank you, experts!

What are the suspension and spring package codes on the RPO sticker under the spare tire cover ?? That will help in diagnosis. Your suspension appears to be monitored, so the car may - may - have an optional suspension system.

I tried to find an RPO sticker.
There was a "SERVICE PARTS IDENTIFICATION" sticker.
There was a VIN? followed by 6KS69 or 6K569.
There was a whole slew of random 3-alphanum codes.
The last line said BC/CC U141D 773.

Does that have the info you need, or do i need all of those other codes?

 

[Submariner409]

Re: 1998 SLS -- suspension codes... need any advice on next steps...

OK - That's the RPO sticker. "Service parts" are more commonly known as RPO - Regular Production Options. Your sticker says what's in YOUR car.

The slew of alphanumeric codes have specific definitions - Google "1998 cadillac seville rpo code list" or something similar.

BC/CC U141D 773 is the paint and interior color ID - BaseCoat/ClearCoat .................... colors in www.paintscratch.com

VIN - Here's the VIN breakdown - but it changes a bit for each model year.

 

[MoistCabbage]

That is the RPO label.

Spring/suspension codes are either FE1 or FE3. If you have CVRSS active suspension you'll also see F45.

 

[basscatt]

Re: 1998 SLS -- suspension codes... need any advice on next steps...

that's quite a colorful novel - oke:

I am really unsure of whether I should have included the CURRENT records or not.
YES - that is very helpful information -

The way that CURRENT vs HISTORY was described initially,
CURRENTs don't always get to HISTORY
unless they recur a number of times,
and are thus validated as
being correct.
wrong -
Current codes are problems that are happening at this moment in time -
History codes are current codes that are no longer happening -


When I am finished, I will come back and detail everything correctly
you will get a lot more help posting the condensed version -

 

[Submariner409]

Yep - a Current code says that something is amiss RIGHT NOW. A particular History code says that at least 3 successful Start-Run-Drive events have occurred without the fault being detected, so it has gone to History (a storage bin) where it remains until (depending on system) 30, 40, 50, 100 successful Start-Run-Drive events have been accomplished with no detection of a particular code - the code then self-clears from the entire system.

The only way you will cross-reference and extensively define a particular code and its abbreviated definition is by using the code lists and diagnostic trees in the GM/Cadillac/Helm service manual set. eBay or www.helminc.com. $300 new, hard copy.

C 1738 - Exhaust solenoid short - The car uses ELC - Electronic Level Control - a compressor/bladder system that compensates for extra weight in the trunk or rear seat. The shocks incorporate air bladders which can effectively change the length of the shock in response to height sensor input to a compressor which supplies/exhausts air as required. The exhaust solenoid is subject to moisture from heat of compression and over time it literally rots. There IS a dessicant dryer canister attached to the compressor/control head assembly, but it overloads and ultimately destroys the system - nasty brown rusty snot is the result. The compressor assembly is up inside the RR wheelwell inner liner. Air lines go to each (rear) shock. There are no front shocks - McPherson struts only. NONE of these cars has "air ride". None. Usually, the first indication of ELC troubles is a dragging tail - leaking shock bladder(s) accompanying a frozen compressor.

Even though it's a "Cadillac" stuff wears out and breaks. Maintenance on most of these (used high mileage) upscale cars is insanely expensive regardless of brand. You will be forearmed if you religiously perform at least weekly underhood checks as well as frequent tire pressure checks - using a good dial gauge and "cold" - tires at ambient temperature.

 

[basscatt]

Re: CORRECTED -- 1998 SLS -- list of codes...

ABS C1255 HISTORY -- EBCM Internal Malfunction
EBCM - Electronic Brake Control Module -
this is the part that controls the ABS - Anti-Lock Brake System -

this is a very expensive part -
if you are lucky - the connector/plug are dirty or corroded -
if not so lucky -
it needs to be replaced or rebuilt -

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

IPM B1340 CURRENT -- Air Mix Door One Movement Fault
the #1 Mix Door controls the cabin temperature on the driver side -
you can try "exercising" the actuator by changing the temperature -
from 60 to 90 SLOWLY - several times -

if that doesn't help -
you will need to replace the actuator -

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

IPM B1344 HISTORY -- HeaterDefrost/AC Door Movement Fault
this is a problem with the MODE door actuator -
the MODE door controls where the air comes from -
floor - center vents - defrost -

similar to the MIX door actuator -
you can try "exercising" the MODE door actuator -
by changing from floor to vents to defrost slowly - several times -

if that doesn't help -
you will need to replace the MODE door actuator -

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

RSS C1711 CURRENT -- Left Front Damper Actuator Short Circuit to Ground
you MUST have F45 - CVRSS Constantly Variable Road Sensing Suspension -
the electronic part of the Left Front strut has malfunctioned -

this is the cause of the CHECK SUSPENSION message -
and the SPEED LIMITED TO 90 message -

you have a several choices -

ignore it - not a good idea -

replace the front struts with the original "ACTIVE" units -
$600+ each - plus labor -

replace the ACTIVE front struts with PASSIVE struts -
around $65 each - plus labor - this is what I recommend -

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

RSS C1738 CURRENT -- Exhaust Solenoid Valve Short to GND
your car has ELC - Electronic Level Control - ALL Cadillacs do -

this system includes special rear shock absorbers that incorporate air bladders -
these air bladders can be inflated to raise the rear of the car -
to compensate for additional loads in the back seat and/or trunk -

other parts of the ELC system are the ride-height sensor -
air lines - and - of course - the air compressor -

your problem is that the exhaust solenoid - part of the compressor assembly -
has failed - and needs to be replaced -

some have been able to rebuild the compressor successfully -
others simply replace it -
new units are available on line for around $240 -

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

regarding your other codes -

"History" codes are no longer "active" - or a problem -
the original problem might have been fixed - and the code never cleared -
or the original problem might have been a "computer glitch"

my advice is to clear the codes and see what comes back -

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

"U" codes are "lost communications with.............."
and can be cleared and ignored - unless the same code comes back often -

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

I tried to find an RPO sticker.
There was a "SERVICE PARTS IDENTIFICATION" sticker.
YUP - that's it - RPO - Regular Production Options -

There was a whole slew of random 3-alphanum codes.
hardly random -
these codes list all the specific options the car left the factory with -
the "build sheet" -

if interested - copy the 3-character codes -
and go here to decipher them -
http://www.cadillacfaq.com/rpo/

 

[bns001]

Submariner409, MoistCabbage, basscatt,

Thank you one and ALL.

I looks like basscatt deduced the suspension and spring package. F45 - CVRSS.

This suspension message has plagued me since I bought this car.
Knowing that there is a "budget solution" and a "duplicate solution" is AWESOME.

Thank you ALL for giving me better ideas of what is involved in starting to get
things fixed.

I will work through all of these suggestions (as budget allows).

Thank you, all!

One last question (for the moment) -- as the issues are fixed, they will "automagically" (after 30, 40, 50, 100 successful Start-Run-Drive events) will fall off of the DTC history?

Peace.

----------

ALL,

according to Submariner409 in #14...
History items are not occurring in last 30, 40, 50, 100 successful Start-Run-Drive events.

So in the future, only post the CURRENT items? Is that correct?

----------

So, I should completely ignore HISTORY records?

----------

oops... Submariners post was 13, not 14.

 

[Submariner409]

Post #2 - "What are the .................". (in reference to RPO suspension codes.) If you had looked them up the F45 and FE3 would have told you the suspension was CVRSS right away.

Post #13 - Codes go to History after 3 successful start-run-drive cycles. Codes that go to history will remain in History for some number of successful Start-Run-Drive cycles after which, if the fault does not occur again, they automatically clear from the system.

It helps to post History codes and their definitions - quite often a system may set several codes, some of which are transient faults.

 

[basscatt]

One last question (for the moment) --
as the issues are fixed, they will "automagically"
(after 30, 40, 50, 100 successful Start-Run-Drive events)
will fall off of the DTC history?
yes - or you could simply clear the codes without waiting -

So in the future, only post the CURRENT items? Is that correct?
NO - always post ALL the codes you have displayed -
and indicate whether each is C - current - or H - history -

So, I should completely ignore HISTORY records?
NO - History codes can be helpful also -

 

[bns001]

Thank you ALL.

Now, I have a list of things to look into fixing... as soon as I can afford it.

 

[basscatt]

Thank you ALL.

Now, I have a list of things to look into fixing... as soon as I can afford it.

==========================
when you are ready - check with us first -

there are several choices on fixing things -
and we can probably $ave you some money -

 

[bns001]

Had a bad time with the car starting Monday evening 6/1 and Tuesday morning 6/2 last week. Also White smoke, and ran rough on 2.5 mile journey.

Was told white smoke is bad and I shouldn't drive the car until I can get someone to look at it.

Today, I was convinced to clear all codes, and test it. Not sure if there was white smoke today.

I got a slightly different list of codes. After test drive, and the car cutting off twice in less than a mile, I ran the codes again --

• (Gone) ABS C1255 HISTORY -- EBCM Internal Malfunction
• AMP U1128 HISTORY -- Loss of Communications with IRC
• DIM B1983 HISTORY -- Device Power Circuit Low
• IPC B1983 HISTORY -- Device Power Circuit Low
• (Gone) IPC B1652 HISTORY -- Loss of Keep Alive Memory (KAM)
• IPM B1340 CURRENT -- Air Mix Door One Movement Fault
• (Gone) IPM B1344 HISTORY -- HeaterDefrost/AC Door Movement Fault
• (Gone) IPM B1652 HISTORY -- Loss of Keep Alive Memory (KAM)
• IPM U1255 HISTORY -- Class 2 Communication Malfunction (Serial Data Line Malfunction)
• (Gone) IRC U1016 HISTORY -- Loss of Class 2 Communication with VCM
• (Gone) PCM P0603 HISTORY -- Control Module Long Term Memory Reset
• PCM P1599 HISTORY -- Engine Stall or Near Stall Detected
• PCM P1626 HISTORY -- Theft Deterrent Fuel Enable Signal Not Received
• (Gone) RIM B1328 HISTORY -- Vehicle system voltage is greater than 15.9 volts
• (Gone) TTM U1300 HISTORY -- Class 2 Short to Ground
• RSS C1711 CURRENT -- Left Front Damper Actuator Short Circuit to Ground
• RSS C1738 CURRENT -- Exhaust Solenoid Valve Short to GND

Thank you all for your help.