Galler

Guys, I know these cars are notorious for electrical problems, and I just ran into what I believe is my first problem.

As I am driving today the following warnings popped up on the cluster:

Serv. tire monitor system (always on at start up)
serv. traction control system
service engine soon
Reduced engine power
low oil
all gauges except tach and speedo died.
ABS light came on
Check engine light came on

Additionally, Windows had no power, and radio and climate control turned off.

Thoughts on where to start? I really hope its something simple like a fuse, but the smarter half of me says something else electrically is wrong.

For the record it is a 1999 FRC with 64,000 miles.

Galler

Thank you, will do.

radracr

I had a very similar situation on my 99 FRC. Someone suggested that I unhook the battery and turn the key from off to cranking about a hundred times to clean the contacts in the ignition switch. So far (about 500 Miles) it has worked to my surprise....might be worth a try.

Smoken1

Why not just clean the contacts in the switch?

Bill Curlee

I had Appendicitis but I took a couple of Oxycodone’s. Now its all better!

LoneStarFRC

If you first remove, then disassemble and clean the contacts properly, I agree.

Bill Curlee

Sounds like you have a corrupted serial data buss. Its pretty common for the LDCM, RDCM or the Seat Control Module to cause your exact issues.

Look in the passengers foot well to the LEFT of the big silver box (BCM) and find the two thin connectors. The connector with FOUR wires connects the LDCM, RDCM or the Seat Control Module serial data wires to the rest of the serial data buss. The TOP of that connector is a shorting bar. Remove the top of the connector and see if the problems go away.



If that solves the issue, you most likely have damaged female pins on one of the connectors for the LDCM, RDCM or the Seat Control modules. Normaly its the door control module connectors that have spread female pins but Ive see the seat connector that get damaged and causes the issues

BC

Galler

Okay fellas, thank you all for the responses and advice. Sorry this has taken all day to get back on here.

The codes are as follows

10-PCM
P1626H, Theft Deterrent Fuel Enable Signal Lost / Theft Deterent System

28-TCS
U1301H, High Voltage on Class 2 Serial Circuit/ Datalink Communications.
U1016H, Normal software function, history status upon ignition cycling/ Datalink Communications

40-BCM
U1255, Lost communications with XXX / Datalink Communications
U1096, Normal software function, history status on ignition cycling/ Datalink Comm.
U1016, Normal software function, history status on ignition cycling/ Datalink Comm.

58-SDM
B1001H , Option Configuration Error / SIR
U1301H, High Voltage on Class 2 Serial Circuit / Data link Comm.

60-IPC
U1255, Lost communication with XXX/ data link Comm.
U1040H, Could Not find what this meant
U1016H, Normal software function, history status on ignition cycling/ Datalink Comm.
U1064H, Normal software function, history status on ignition cycling/ Datalink Comm.
U1088, Loss of communication with SDM, refer to U1001-U1254 Loss of communication with XXX IPC / Datalink Communication
U1176H, Lost communication with RFA
U1160H, Lost communication with SCM

80-Radio
U1096H, Normal software function, history status on ignition cycling/ Datalink Comm.
U1016H, Normal software function, history status on ignition cycling/ Datalink Comm.
U1064H, Normal software function, history status on ignition cycling/ Datalink Comm.

BO-RFA
U1255H, Lost communication with XXX/ Data link Communication
C2120HC, TPM System Malfunction/ Tire pressure monitoring


Thoughts? Suggestions on Places to start, Other than previous post?

Bill Curlee

Well,,, Now that you know what DTCs you have,, CLEAR ALL OF THEM and see what comes back. We will go from there.

Bill

Galler

Alright done, Cleared everything, turned ignition all the way off then back to run, and brought up diagnostics, NO CODES. Turned the engine on, let it run, within 15 seconds all warnings started again. Turned off engine ran diagnostics. every code listed above with the exception of the following appeared again in DTC

58 SDM : B1001
60 IPC : U1160
BO RFA : C2120

Bill Curlee

Do what I recommended in post#9 See if that clears up the Serial data buss codes and all the rest of the stuff.

Bill

Galler

Will do, probably won't get to it till late tomorrow or Friday morning but will let you know ASAP

Thanks for your help so far

Galler

Alright, So I had a list of work to do today on the FRC. Eventually got to the electrical issues. I pulled off the connector bar. And it cleared up almost all of the issues. I was having however one old and a second new still persist.


Windows still have no power, and now my Oil Pressue gauge is reading 115 PSI at idle. (both analog gauge and DIC)

DarioC

That picture of the connector reminded me of a problem that we ran into in the electronic calibration business years ago. It may or may not be relevant to this problem, but it is a good thing to know about in this age of electronic gizmos on everything.

We found that a "clear" corrosion (we never could see it) would form on the nickle plated battery contacts on some Volt-Ohmmeters. The meter would go intermittent on the Ohms range. The operating voltage in that circuit was 1.5 Volts.

We corrected the problem by applying a thin coat of light oil to the contacts with a Q-tip.

Last year I saved myself about $300 bucks when a repairman was going to replace my Furnace-AC controller and I corrected the problem on my controller plug-in unit using this method. So the problem is still likely to show up on plated contacts in lots of other applications.

I suspect that at lower voltages one will likely see the problem more often, as in the small signals common to various sensors and perhaps some data lines.

Hope this information with useful to someone out there.

DC

Bill Curlee

If that made a major improvement, you need to pop the door accordion tubes out and pull the connectors out of the body A pillar. The female pins in the connectors are damaged and spread apart. Bend them back in shape.

Examine the seat connector for the same issue.

What are the other DTCs

Your Oil Pressure Sensor is bad. Change it.. Very common.

Bill

LoneStarFRC

Excellent points. Very low level signals (both voltage and current), such as those typically found on serial data busses, are MUCH more susceptible to even the slightest increase in circuit resistance from either corrosion OR poor contact.

Far too many people today, CONTINUE to jam DVOM probes into contacts, connectors, etc, when taking readings or otherwise doing their troubleshooting, and in so doing actually CREATE problems where many times it did not previously exist. The GM FSM is FILLED with warnings about this issue and the need to use proper methods when doing electrical troubleshooting, and yet people often continue to use "old school" methods, usually by jamming probes into connector pins or terminal contacts, and then wonder why they continue to have problems.

MSUGTO

I had something similar happen and spraying contact cleaner in the connection right in the door jam fixed it.

Galler

Will do, Am I to leave the shorting bar unhooked permanently then? will also post pic shortly as my female end looks as if it is missing connectors.

Galler

The image posted by Bill shows more metal connectors than in mine, I apologize for bad lighting but mine only has metal connectors on the far right, openings 2 and 3 from the right and opening 3 from the left

Galler

Should also note, no current codes come up