Are you 100% sure that the connections on the starter solenoid are clean and tight and not damaged??

BC

 

I cleaned them but it seemed a formality since they looked fine when I took them off. I used a coarse scotch-bright pad and added some dielectric grease before putting them back. Fitting a torque wrench up there was impossible but I got a box-end wrench up there and put decent elbow grease into it. My confidence level is high.

On a somewhat related note, I have a question... When a parts store (NAPA in my case) does a bench test of an alternator, does it test the communication with the L and F terminals, or does it just look to see how it does under load (output only)?

I am no expert, but seems to me I am looking at a bad alternator (poor comm to/from L and F terminals) or a bad PCM.

My girlfriend reminded me today of how the "Charge System Fault" first reared its ugly head in 2009. I was out of town on an extended assignment, so I was out of the picture. A friend needed a loaner car and I told him to take it. Huge storms rolled through and he returned the car to my house when the streets were pretty deep with rain water. The GF says he pulled onto my street while the water was still "pretty high". It may have been high enough to reach the PCM and/or the starter solenoid. Not sure. The only thing approaching a quantitative description of the water level was her remark that he was "plowing water" as he pulled in.

Having looked at the red and blue connectors at the PCM this weekend, I can say they are spotless inside. Like a clean room. Ditto for the splice pack behind the battery. Factory fresh.

There is corrosion on the exterior of the PCM. Keep in mind I had a battery terminal leak last year.

I'm rambling. Sorry.

I am tempted to buy another alternator. I just can't bring myself to let a dealership look at my PCM or replace it just yet.

Thanks a ton,

-Dave
-------------------------------------------
------------ UPDATE 03/28/11 ------------

The car sat overnight. Oil temp at 54 this morning when started. Car had sat for 11 hours. No "CHARGE SYSTEM FAULT" (1638) code. 16 miles to work and it didn't come up even once.

Checked for other codes when I got to work and it showed only B0-RFA: U1064H.

What exactly is "B0-RFA"? I know RFA is "Remote Function Actuation", but it's pretty much greek to me. Wondering if this points to something specific that I might be able to track down.

Thanks again,

-Dave

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

 

The BO-RFA is a loss of communication with transmitters - possibly because you had the battery disconnected!
EDIT: Wheel sensors or Key Fobs etc.

Now as far as your procrdure - The only thing I noticed was the use of DIELECTRIC grease on the starter solenoid connections -

As a note DIELECTRIC grease "DOES NOT" promote better connetivity (Metal to Metal), all it does is aid in keeping corrosion away, and moisture away that will destroy connections - if too much was used, say under the positive cable to the starter solenoid, it may hinder connectivity and current from battery to and from starter etc.

So make sure you don't have too much and make sure you have a clean metal to metal marriage between your positive cable and starter and any other areaa under question.

It does sound like you are on the right path with this mornings results - keep us informed as to anymore progress or problems

Thanks,Matt

 

I had cleared all the codes yesterday, so the "B0-RFA: U1064H" must have cropped up this morning. I'm guessing it happens right at start-up.

I'm much more concerned about the P1638, since it shows up in the DIC whenever the code is set. I did not use much dielectric grease and the contacts look great, so I think the risk there is low.

Just not sure what to work on next.

Thanks.

 

4 days now and no 1638 code!

5 days ago I added the battery-to-alternator cable and the extra engine ground. Why it took a day for it make a difference I'n not sure. I don't really care as long as it's gone.

I still get a U1064 code, but of course that does not propagate to the DIC, so it's no big deal. That code must register when I start the car because no matter how fast I check the codes it's always an "H" (Historical).

Thanks Bill and Matt!

 

That's excellent - it took time for the History part to clear, on/off cycles

Glad it is working good now

Thanks,Matt

 

I'm getting Active Handling and Reduced Engine Power non-stop.
1514 (TAC System MAP Perf) and 1278 (TCS Temp Inhibit by PCM).
Going to clean and change the grounds.
Maybe I need a new TAC module?

 

Grounds dont have much to do with this issue. Heres the write up on the DTC:

DTC P1514 Throttle Body Performance
Circuit Description
The PCM uses the TP, the BARO, the IAT and the engine RPM in order to calculate an expected Mass Airflow rate. The PCM compares this value to the Mass Airflow value and the speed density calculation in order to verify the proper throttle operation.

Conditions for Running the DTC
DTCs P0601, P0602, P0606, P1515, P1516, P1517, P1518, P1624 are not set.
DTCs P1120, P1220 and P1221 are not set at the same time or DTCs P1120 and P1220 are not set at the same time.
Engine operates longer than 1 second.
Engine speed is greater than 500 RPM.
Conditions for Setting the DTC
The PCM detects that actual airflow (MAF) and Speed Density is much greater than the expected (calculated) airflow rate.
All above conditions met for less than 1 second.
Action Taken When the DTC Sets
The PCM will illuminate the Malfunction Indicator Light (MIL) when this diagnostic runs and fails.
The Reduced Engine Power message displays on the drivers information center.
The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Freeze Frame and/or Failure Records.
If no other TAC System DTCs are set, the TAC System operates in Reduced Engine Power mode, and this DTC will be stored. If certain TAC System DTCs are set at the same time, the TAC System either defaults to a more tightly restricted mode of operation if the TAC determines that limited safe operation is possible, or the TAC commands the engine to shut down.
Conditions for Clearing the MIL/DTC
The PCM turns the MIL OFF after three consecutive drive trips that the diagnostic runs and does not fail.
A last test failed (Current DTC) will clear when the diagnostic runs and does not fail.
A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
The PCM battery voltage is interrupted.

Important
The clear DTC info function may have to be performed twice in order to clear a Throttle Actuator Control System DTC.


Clear the MIL/DTC information using a scan tool.
Diagnostic Aids

Important
Remove any debris from the PCM\TAC module connector surfaces before servicing the PCM\TAC module. Inspect the PCM\TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM\TAC modules.


Inspect the throttle blade for being broken, bent or missing.
Inspect the TP sensor for proper installation. A sensor that is mis-aligned sets this DTC.
For an Intermittent condition refer to Symptoms .
If a repair is completed and the DTC was cleared using a scan tool on the same ignition cycle, the default action will not clear until an ignition cycle has occurred.
When the TAC module detects a problem within the TAC System, more than one TAC System related DTC may set. This is due to the many redundant tests run continuously on this system. Locating and repairing one individual problem may correct more than one DTC. Keep this in mind when reviewing captured DTC info.
Test Description
The numbers below refer to the step numbers on the diagnostic table.

Physically/visually inspect the throttle body assembly and correct any problems that you observe. Manually move the throttle blade from closed to Wide Open Throttle (WOT). You should not need to use excessive force. The throttle blade should move smoothly through the full range and should return to a slightly open position on its own.

When the TAC module detects a problem within the TAC System, more than one TAC System related DTC may set. This is due to the many redundant tests run continuously on this system. Locating and repairing one individual problem may correct more than one DTC. Keep this in mind when reviewing captured DTC info.

DTC P1514 - Throttle Actuator Control (TAC) System MAF Performance Step
Action
Value(s)
Yes
No

1
Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?
--
Go to Step 2
Go to Powertrain On Board Diagnostic (OBD) System Check

2
Is DTC P0101, P0102, P0103, P0107, P0108, P0112, P0113, P1111, or P1112 set?
--
Diagnose these DTCs first
Go to Step 3

3

Caution
Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.



Important
If any of the conditions listed below exist, replace the throttle body.


Inspect the throttle body for the following:

TP sensor loose or damaged
Loose or damaged throttle blade
Broken throttle shaft
Drive mechanism damage
Did you find and correct the condition?
--
Go to Step 4
Go to Diagnostic Aids

4
Select the Diagnostic Trouble Code (DTC) option and the Clear DTC Information option using the scan tool.
Start engine and idle at normal operating temperature.
Select the Diagnostic Trouble Code (DTC) option and the Specific DTC option, then enter the DTC number using the scan tool.
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text, if applicable.
Does the scan tool indicate that this diagnostic ran and passed?
--
Go to Step 5
Go to Step 2

5
Select the Capture Info option and the Review Info option using the scan tool.

Does the scan tool display any DTCs that you have not diagnosed?
--
Go to the applicable DTC table
System OK



--------------------------------------------------------------------------------
Document ID# 203731
1998 Chevrolet/Geo Corvette


Check the TB and Throttle Position Sensor first. What Mods do you have?

BC

 

Wow. Thanks man.
I'll look into what little of that I understand!
As for mods... I've pretty much got them all.
Built ls7, monster cam, lpe 4" intake/maf, nw 104 tb, fast 102, 3" pipes
...etc. Run off a 2000 PCM.
Only recent mods are bbk
And cf hood which is clearly rubbing on the intake near the maf! Wah!

 

Need to get rid of those ground packs nOnetheless as my louvered hood also drips water right onto them and I drive in Canadian salt with no wheelwell liners! Ack!

 

i have a 2000 convertible i just purchased . while i was making some upgrades i changed all the bulbs to led , installed a alarm and a high end stereo system complete head unit amps new speakers used none of the old system. when i first drove the car when i hit the brake the dash and parking lights flash super fast and when i use the key fob to lock the horn starts blowing . if i turn on my parking lights the flashing stops (maybe it doesnt but with lights on you cant tell). i purchased a hyper led flash unit havent installed yet but does anyone have any ideas

 

LED replacement lights draw VERY LITTLE current co your BCM thinks that the bulbs are blown. Im not a LED fan so, I have little or no expierence with them but I do know that you have to install a LOAD resistor in series with the LED bulb units. Some people just use a standard light bulb tucked away somewhere.

People have resolved this issue. Just have to find someone who has done it and figure out the best method. Dont know if the hyper unit will help with that issue.

Bill

 

Bill,

I'm getting the same code for a few modules: U1064. I get this code for the LDCM, RDCM, and SCM. I also get a 2262 for the LDCM.

Do these sound like issues with the modules themselves in the door?

I'm going to clean the ground near the battery compartment but it doesn't appear to be that dirty.

Any tips would be much appreciated.

Thanks,

Rick

Thanks,

Rick

 

The most prevalent cause of the U series DTCs are caused by a very brief loss of power.. One of the things that can cause this problem is a poor connection in one of the effected modules. First pull the accordion tubes and pull the door harnesses out of the door FRAME. Disconnect the power connector and look for bent female pins like this:



Bend the bent pin back in place with a metal pick.

Do the same for the seat connector.

Bill

 

Bill,

Really appreciate the response. I will give this a try and go from there. Thanks again.

Rick

 

Please post results positive or negative. Post pictures of your connectors if you can Recommend you check BOTH DOORS.

Bill

 

Which underhood fuse do I pull to disable AH/ABS (BCM I suppose?)?
Read it in here somewhere but cant remember or find it now.
What else does the BCM control?
Thanks

 

Definitely will. May be a few days as I'm waiting on spark plug wires and unable to get to the passenger door.

 

Hi Bill,
I am having the same problem on my 03. It did this a year ago the dash goes crazy windows, mirrors dont work and I was able to fix it by playing with the connections in the drivers door. Well now its back, I can move a wire in one of the connections to get everything working on the drivers side but cant get the passenger side working. Can you help ?
Thanks Dino

 

Disassemble the door connectors and fix the bad bent nasty female pins.

Bill