mpostr Posted August 23, 2006 Report Share Posted August 23, 2006 I've recently been getting a "Speed limited to 90" message on my 99 Seville STS. The stored DTC's are C1252, C1253, and U1255. I suspected the CVRSS module as the culprit after reading some old threads in this forum, but took it to my local dealer to confirm my diagnosis before I bought a module. After $120 diagnosis charge, they concurred, so I bought a used module (since new ones are $900+). After installation I get the same DTC's. So either I bought another bad module, or the problem is elsewhere. About one year ago I installed passive struts from Boston Suspension and have had no problems and no RSS messages. Could a problem have developed with this conversion that is causing the DTC's I'm getting now? Where should I be looking to eliminate the current problem? Any suggestions, or thoughts would be appreciated. Link to comment Share on other sites More sharing options...
JimD Posted August 23, 2006 Report Share Posted August 23, 2006 Your C1252 and C1253 codes are set by the EBTCM, not the CVRSS. First suspect is the EBTCM connector and chassis wiring harness. Check for loose or corroded or damaged or wetted by something other than clean water. Do these codes appear immediately after you clear them? Or, what type of road surface causes the 'speed limited' message to appear? Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
mpostr Posted August 23, 2006 Author Report Share Posted August 23, 2006 The codes appear immediately after they are cleared. Link to comment Share on other sites More sharing options...
JimD Posted August 23, 2006 Report Share Posted August 23, 2006 Do you get the 'speed limited' message immediately on start (gear selector in Park)? Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
The Fred Posted August 23, 2006 Report Share Posted August 23, 2006 Someone was talking about this the other day You might find the thread with search As a matter of fact here it is. http://caddyinfo.ipbhost.com/index.php?showtopic=4931 MerryChristmas Be a Capitalist or work for one. Work for a Capitalist or be one. MerryChristmas Link to comment Share on other sites More sharing options...
mpostr Posted August 24, 2006 Author Report Share Posted August 24, 2006 JimD, The message appears immediately after starting the car - with the gear selector in Park. Link to comment Share on other sites More sharing options...
JimD Posted August 24, 2006 Report Share Posted August 24, 2006 .... About one year ago I installed passive struts from Boston Suspension and have had no problems and no RSS messages. Could a problem have developed with this conversion that is causing the DTC's I'm getting now? Anything is possible, but I doubt the C1252/3 codes are related to the passive struts. Other suspension codes would tell you if the work-around for the strut damper valve has failed. It is important to eliminate any possibility this is a damaged wire harness or connector problem. Start at the CVRSS and inspect for obvious wire damage. Pull the connectors and carefully check the chassis harness for connector pins that are bent, corroded or pushed out of position. A magnifying glass and bright light will help a lot. Then do the same inspection at the EBTCM cable harness and connector. Have you had any intermittent / random ABS related codes in recent months? To indulge my own curiosity, can you describe how Boston Suspension fooled the CVRSS into believing that a strut valve was actually installed? Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
mpostr Posted August 25, 2006 Author Report Share Posted August 25, 2006 Jim, I'll go over the wiring harness and connections before I replace the EBTCM module. The engine was out a couple months ago for head gasket replacement. Maybe a wire got snagged, or a ground wire left loose in the process. The Boston Suspension package uses regular struts and air shocks and they supply you with (4) 12 ohm, 50 watt power resistors that you splice into the harness after you cut off the strut connector ends. It works well. I've not had any RSS codes since making the modification. Link to comment Share on other sites More sharing options...
JimD Posted August 25, 2006 Report Share Posted August 25, 2006 .... The engine was out a couple months ago for head gasket replacement..... That is a red flag. Since it took some time for these codes to appear, I would suspect the chassis harness that connects to the EBTCM. Follow that bundle of wires looking for loose tie downs where there is an opportunity for rubbing, chafing or pinching due to movement. Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
JimD Posted August 30, 2006 Report Share Posted August 30, 2006 Any additional feedback?? Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
mpostr Posted August 31, 2006 Author Report Share Posted August 31, 2006 I've been tracing wiring and checking connections from the EBTCM, but haven't found anything that looks suspect yet. The harness is still secured in conduit and no signs of rubbing, melting, cracking, etc. The dealer tech that diagnosed it for me said that the only other thing it can be is the EBTCM if it's not the CVRSS module. He claims to have checked all of the wiring. I've obtained a used EBTCM, but have not installed it yet. I'd like to be sure it's causing the problem before I install. Link to comment Share on other sites More sharing options...
mikeal1892 Posted September 2, 2006 Report Share Posted September 2, 2006 HMMMMMMMMMM ! Well now this is something I know something about... umm I bought my car over 2 years ago with a suspension issue I was getting a C1711 I think thats what it was. I replaced that left front strut with one from a high end used parts place out of northern Indiana. Prior to doing so sometimes it would be fine but mine done just like yours is doing and flashed the speed was limited. I honeslty think that got to me more than the ses light ... My suspension computer on the back wall behinde the backseat wall on the pass side was bad. BBF (mike) told me about Car-part.com and I was able to buy one after pirnting out a list of 20 places....lol I called them all and the last one had the matches letters on the box. that tells how your suspension is tuned. $30.00 for a part that I could get at cost for 7 or $800 it was I forget what mine was now.. I love my active suspension and I feel its worth having ! Michael- Link to comment Share on other sites More sharing options...
mpostr Posted September 2, 2006 Author Report Share Posted September 2, 2006 I obtained a used EBTCM with the ABS modulator valve already attached. After clearing the codes, I connected the wiring harness to the EBTCM. Just as before, I immediately get my "Speed limited to 90" message. The codes are the same; C1252, C1253, and U1255. I also get a host of other codes since the ABS modulator and brake lines were not connected to the"new" part. The EBTCM and CVRSS are well-grounded. I don't want to take it back to someone that doesn't know what they're doing and wind up paying them $60/hour. I'm frustrated!!! Link to comment Share on other sites More sharing options...
JimD Posted September 2, 2006 Report Share Posted September 2, 2006 We can understand the frustration. Because the engine has been out AND the U1255 seems to be consistent, I would expand the connector and cable harness damage search to include all the wiring to and from the PCM. Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
mpostr Posted September 9, 2006 Author Report Share Posted September 9, 2006 I haven't completely given up trying to fix my problem (but it's tempting) so I'm reaching for possibilities. After replacing the CVRSS and EBTCM modules (with used components) I still get C1252, C1253, and U1255 codes immediately upon turning the ignition on. Fortunately, I've been able to return the modules. I've talked with the technician who diagnosed the car and he insists that the wiring checked out okay. The used CVRSS module I installed came from a 99 SLS. My car is a 99 STS. He thought that possibly the SLS module could be bad also, or perhaps the programming for an SLS is not compatible with the STS, or perhaps the SLS did not have Stabilitrack as mine does. He suggests trying a different module. Does anyone know if the difference between the SLS and STS ride programming could make the modules incompatible? Did all Sevilles of that year have Stabilitrack? I know it's entirely possible the modules I purchased could also be bad, but I'm unsure as to these other possibilities. Link to comment Share on other sites More sharing options...
Cadillac Jim Posted September 9, 2006 Report Share Posted September 9, 2006 The code U1255 - Class 2 Communication Malfunction (Serial Data Line Malfunction)tells us that you have a wiring problem. It is between the PCM and the CVRSS computer (you've already eliminated the modules themselves). That will cause the other codes and the DIC message. In any case, you need to clear the U1255 problem before you can go farther. -- Click Here for CaddyInfo page on "How To" Read Your OBD Codes-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data -- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC Yes, I was Jims_97_ETC before I changed cars. Link to comment Share on other sites More sharing options...
JimD Posted September 9, 2006 Report Share Posted September 9, 2006 There are two ground connections to inspect carefully for wires broken or pulled out of the ground block. One is identified as G102 and is located at the LR corner of the engine near the Park-Neutral safety switch. This is my favorite suspect because the engine has been removed and replaced. The other is G401 located at the lower left corner of the trunk near the wheelhouse. Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
mpostr Posted September 9, 2006 Author Report Share Posted September 9, 2006 JimD, Is the G102 location you're talking about grounded to the engine block? If so, I've located it, but it is EXTREMELY difficult to get to without dismantling a lot of the top-side components. Is there an easier way? I've located a G104 in the trunk behind the passenger tail light, but will check for one on the LR wheelhouse as you suggest. Link to comment Share on other sites More sharing options...
JimD Posted September 9, 2006 Report Share Posted September 9, 2006 I can't even see G102 on my '98. The safety switch, heater hose, master cylinder and vacuum boost are all blocking the view . I would try from the bottom looking up. Jim Drive your car. Use your cell phone. CHOOSE ONE ! Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.