1999 Coupe
LS1 Auto
All options (except Z06).
70,000 miles.

This started a few weeks ago.
I checked the grounds under the hood and checked the footwell, connectors in each door opening loom as referenced in that thread.
I cleared all codes and drove into work.
Here is what I ended up:

10-PCM P1626 H P1652 H
28-TCS U1301 H U10116 H
38-RTD NO CODES
40-BCM B2578 H B2583 H U1255 H U1096 H U1016 H
58-SDM U1301 H U1016 H U1096 H
60-IPC U1255 H U1040 H U1016 H U1064 H U1176 H U1088 H
U1056 H U1160 H

80-RADIO U1096 H U1064 H U1016 H
99-HVAC U1064 H U1096 H U1160 H U1255 H
A0-LDCM B2262 H B2264 H U1255 H U1064 H U1016 H U1096 H
A1-RDCM U1255 H U1064 H U1016 H U1096 H
A6-SCM U1300 H U1016 H U1064 H
BO-RFA U1255 H U1096 H U1064 H U1016 H

Driver Info System
SERVICE ACTIVE HNDLG
SHOCKS INOPERATIVE
SERVICE TRACTION SYS
SERV. TIRE MON, SYS
REDUCED ENGINE POWER
CHECK TIRE PRESSURE
SERVICE VEHICLE SOON

Dash Lights
Security
Traction Control
Check Gauges
ABS
Air Bag

Also
all gauges stop working, just as if the ignition key was turned off.
Car runs fine through all of this.
Battery was replaced 3 months ago and connections are secure.
Just point me in the right direction.

 

Awesome, thanks, I'll go down that road tonight.

 

I agree that the ign switch is a good possibility. Why are all the codes you show H and no C? I would think a NO COMM to a module or some IPC and BCM codes would surely be current?

 

 

Check the connections at the starter solenoid too for anything lose or burned insulation indicating a lose connection. Clear the codes and see what comes back.

 

This may not apply, but when reflashing the ECU with HPT the key needs to be cycled afterwards or things go crazy. So if you have been doing some tuning recently and forgot to cycle the key after the upload it can cause things like this. (I found out the hard way and FREAKED out)

 

No tuning, car is stock.
Problem started back in February with the "Shocks Inop" message sporadically and progressed to the "Service Traction System" and the 80 MPH warning sporadically, and increased in frequency over time to all of the symptoms in my original post. It seems to be a product of time in that short trips of 10 or 15 mins around town produce no msgs or lights. Commuting my 28 miles one way will usually produce a msg or warning after 40 mins or so of highway cruising (72 with the cruise control on). The shock inop msg will always appear first, then the traction msg followed by one or all of the others. The car runs and drives fine through all of this, although at times, it does feel like the shocks are not working at all. It is always set to the "Sport" mode and switching between the three setting has had no effect on the msgs or warning lights.

I will not have time to troubleshoot the ignition switch until this weekend. I will post results.
Thanks -

 

I have almost exact same symptoms- lots of codes. HOWEVER, my engine sometimes develops a rough idol, and my speedo and tach gauges bounce- but they're not dead like yours are. This problem comes and goes. Never have starting problems though. the other day it got worse and wouldn't idol. Need to keep RPMS up over 2000 to keep it from stalling.

cleaned MAF, changed plugs, wires, air filter. Did not check fuel pressure or replace fuel filter yet.

DIC indicates 12.1 when engine is off and 14.5 when running. this never drops.

I will keep you updated, can you mention here if you find anything. I'm tearing into it tomorrow.

Thanks
j

 

OK, I performed all the ignition switch checks and all is as it should be. I have followed and performed everything in the sticky DIY thread under post #66. Don't know where to go next so I will start over from square one and make sure I touched everything.

 

and I forgot to mention the codes for A0-LDCM can not be cleared. I push reset and it beeps and blinks, then these codes are displayed again:
B2262 H B2264 H

 

If you CLEAR ALL of those DTCs when the problem happens again, post what returns

Check the battery terminals. They MUST be clean and tight. Proper torque for a 97-03 is 11 ft/lbs

If you can move the battery cables on the battery by hand,,,, there TOO LOOSE!

 

Thanks Bill, I will do both. I did replace the battery in February and it is interesting in that the battery voltage drops from 12.4 down to 11.2 in the 20 mins or so I had the key on checking the fuse voltages. All acc. were turned off too.

 

Could be the star connector located in the passengers foot well. All the modules communicate through that connector so if you are getting all these weird messages and loss of comm that could be it. I have replaced a star connector for a similar issue and it fixed it.

 

I'll take another gander at the star connector too, Thanks.

 

it may not appear to be bad, you can try swapping the male portion of the star connectors with each other.

 

has anyone else heard that these electrical issues are caused by the lead free solder? I was told some solder joints get brittle, (almost like a cold solder joint), so that connections that appear good will cause mystery symptoms...

an electronics tech buddy, resoldered all of my circuit boards with some old fashioned solder he had laying around...

word of warning... unless you have the heat sinks, micro soldering tools, "do not attempt"

 

OK - I rechecked all of the grounds except the ones in the body pillars, and all are clean and tight.
I unplugged and plugged back in the BCM and the SCM and verified the battery cables are clean, and tight, and that the OEM cable ends seal like they were designed.
I cleared all DTCs and drove the 28 miles of freeway to work.
This is what I had at the end of that trip:
40 BCM
B2578 H
B2583 H
The turn signals and flashers work fine by the way and there were no lights or nasty messages on the display. I cleared those and we'll see what the drive home produces.
Thanks -

 

Well I have a problem also my passenger seat makes a clicking noise. Does any body know whats wrong??

 

Well,, Delphi electronics SUCK. Ive seen 10 year olds solder better!

YES,, LOTS of circuits have POOR solder joints and the HVAC Control Head have resistors that just POP OFF the board and you loose the back lighting and Florescent display!!

BC

 

For the codes you posted...

DTC B2583 Left Front Turn Signal Monitor Circuit




Circuit Description
The BCM monitors the LF turn signal circuit in order to determine the status of the turn signal switch. If the BCM detects an oscillating voltage on CKT 14, the BCM interprets this as a LF turn signal ON request from the turn signal switch. The BCM will de-energize the LH DRL relay, which will disable the LF turn signal lamp (which is ON for the DRL), thus allowing the LF turn signal to flash. If the BCM does not detect an oscillating voltage on CKT 14, the BCM interprets this as the LF turn signal being OFF. The BCM will then energize the LH DRL relay and continue normal DRL operation. The BCM monitors the LF turn signal CKT 14 and determines how long voltage is applied. If the voltage is applied for longer than expected, a malfunction is present and a DTC will set.

Conditions for Setting the DTC
• The BCM detects continuous battery voltage on the LF turn signal monitor circuit (CKT 14).

• The condition must be present for longer than 5 seconds.

Action Taken When the DTC Sets
• Stores a DTC B2583 in the BCM memory.

• No driver warning message will be displayed for this DTC.

Conditions for Clearing the DTC
• This DTC requires an ignition cycle in order to change from current to history.

• The BCM no longer detects continuous battery voltage on the LF turn signal monitor circuit (CKT 14) for longer than 5 seconds.

• A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no longer present.

• Use the IPC clearing DTCs feature.

• Use a scan tool.

Diagnostic Aids
• The following conditions may cause an intermittent malfunction:

- There is an intermittent short to voltage in CKT 14, CKT 16, or CKT 1314.

- The turn signal switch or the hazard switch is shorted internally or is sticking.

• The BCM needs to detect voltage oscillations on CKT 14 in order to de-energize the LF DRL relay. If the BCM detects continuous voltage on CKT 14, the BCM interprets this as a short to voltage. The BCM will continue with normal DRL operation, and the LF turn signal will remain inoperative.

• If the DTC is a history DTC, the problem may be intermittent. Perform the tests shown while moving related wiring and connectors. This can often cause the malfunction to occur. Refer to Intermittents and Poor Connections Diagnosis .

Test Description
The numbers below refer to the step numbers on the diagnostic table:

This test will check if a DTC B2578 is stored in the BCM memory.

This test will determine if there is a short to voltage in CKT 14.

This test will determine if there is a short to voltage in CKT 1314.

This step tests for an internal short in the DRL relay.

This test determines if the short to voltage is located in the hazard warning switch.

This test determines if the short to voltage is located in the turn signal switch.

This test determines if the short to voltage is located in the I/P.

DTC B2583 -- LF Turn Signal Monitor Circuit Short to Voltage Step
Action
Value(s)
Yes
No

1
Were you sent here from the BCM Diagnostic System Check?
--
Go to Step 2
Go to Diagnostic System Check - Body Control System

2
Using a scan tool, check for BCM DTC B2578.

Is DTC B2578 stored in the BCM memory?
--
Go to Step 14
Go to Step 3

3
Turn OFF the ignition switch.
Disconnect the LH DRL relay.
Turn ON the ignition switch.
Turn OFF the turn signals.
With a test light connected to ground, probe CKT 14 at the I/P electrical center LH DRL relay terminal. Refer to Power Distribution Schematics in Wiring Systems for electrical center identification.
Is the test light ON?
--
Go to Step 6
Go to Step 4

4
With a test light connected to ground, probe CKT 1314 at the I/P electrical center LH DRL relay terminal. Refer to Power Distribution Schematics in Wiring Systems for electrical center identification.

Is the test light ON?
--
Go to Step 13
Go to Step 5

5
Check for continuity between the LH DRL relay terminals 4 and 5 (or 87 and 87A).

Is there continuity?
--
Go to Step 17
Go to Step 9

6
Turn OFF the ignition switch.
Disconnect the hazard warning switch connector.
Turn ON the ignition switch.
With a test light connected to ground, probe CKT 14 at the I/P electrical center LH DRL relay terminal. Refer to Power Distribution Schematics in Wiring Systems for electrical center identification.
Is the test light ON?
--
Go to Step 7
Go to Step 16

7
Turn OFF the ignition switch.
Disconnect the turn signal switch connector C211.
Turn ON the ignition switch.
With a test light connected to ground, probe CKT 14 at the I/P electrical center LH DRL relay terminal. Refer to Power Distribution Schematics in Wiring Systems for electrical center identification.
Is the test light ON?
--
Go to Step 8
Go to Step 15

8
Turn OFF the ignition switch.
Disconnect the IPC connector.
Turn ON the ignition switch.
With a test light connected to ground, probe CKT 14 at the I/P electrical center LH DRL relay terminal. Refer to Power Distribution Schematics in Wiring Systems for electrical center identification.
Is the test light ON?
--
Go to Step 11
Go to Step 12

9
Inspect for the following intermittent malfunctions:

• A short to voltage on CKTs 14, 16, or 1314.

• An internal short in the LH DRL relay.

• An internal short in the turn signal switch.

• An internal short in the hazard warning switch.

• A short at IPC terminal A14.

Was a problem found and repaired?
--
Go to Step 19
Go to Step 10

10
Turn OFF the ignition switch.
Reconnect or install any connectors or components that were disconnected or removed.
Turn ON the ignition switch.
Clear any DTCs. Refer to Clearing DTCs .
Wait 5 seconds and check for DTCs.
Does DTC B2583 set as current?
--
Go to Step 18
System OK

11
Locate and repair the short to voltage in CKT 14.

Is the circuit repair complete?
--
Go to Step 19
--

12
Locate and repair the short to voltage at the IPC connector terminal A15.

Is the circuit repair complete?
--
Go to Step 19
--

13
Locate and repair the short to voltage in CKT 1314.

Is the circuit repair complete?
--
Go to Step 19
--

14
Check for a short to voltage in CKT 16.

Was a condition found and repaired?
--
Go to Step 19
Go to Step 16

15
Replace the turn signal switch. Refer to Multifunction Turn Signal Lever Replacement - On Vehicle in Steering Wheel and Column.

Is the replacement complete?
--
Go to Step 19
--

16
Replace the hazard warning switch. Refer to Hazard Warning Switch Replacement in Lighting Systems.

Is the repair complete?
--
Go to Step 19
--

17
Replace the LH DRL relay.

Is the replacement complete?
--
Go to Step 19
--

18
Replace the BCM. Refer to Body Control Module Replacement .
Program the BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration .
Is the replacement complete?
--
Go to Step 19
--

19
Turn OFF the ignition switch.
Reconnect or install any connectors or components that were disconnected or removed.
Turn ON the ignition switch.
Clear any DTCs. Refer to Clearing DTCs .
Is the repair complete?
--
Go to Diagnostic System Check - Body Control System