I got a 1.2 = error code 41?

And in 9 = 64(TPS error)

On the 1st error, how can the ECM lose communication and still run?

On the 2nd, what is the TPS on the ASR/ABS?

TIA

 

Ok, can someone please tell me where to findout what these codes mean?

 

Pull the code. http://www.troublecodes.net/GM/

Once you get the number...post it here.

 

Turn ignition switch to OFF position
Locate Data Link Connector (DLC),
Jumper the A&B terminals(a paper clip or a jumper wire work ok) in the shape of a U
Turn Ignition switch to ON position.
Count the flashes on the "CHECK ENGINE" or "SERVICE ENGINE" light.
FLASH, pause, FLASH, FLASH = code 12

 

They were on the 1st part of the thread,
CCM error 41
ABS/ASR 64

 

http://forums.corvetteforum.com/member.php?u=209623

 

If you are talking about a loss of "serial communications" between the ECM and CCM, it is because the ECM can run the engine "standalone" once the engine is started (however, you will frequently see a SYS and possibly the "Security" flashing).
The ECM needs to communicate with the CCM, for security reasons, in order to start the car, but once the car is started, it will not shut down because of a failure in the serial link.
When I got serial-link errors on my '92, the ECM was the problem.
I'm told the '92 and '93 ECMs are notorious for this problem.
Mine would only happen after the engine warmed up enough to heat the ECM under the hood.

The TPS sends a signal to the ECM and to the TPS buffer (this is the square thing by the windshield washer fluid reservoir), and the TPS buffer sends the throttle position information to the ASR/ABS unit.

Tom Piper

 

Thanks Tom!!
Could the TPS error been caused by the Communication error?
I am beginning to know the manual a little to well or maybe not enough, I not sure which!!

 

I doubt if the TPS error has anything to do with the communications error unless you have a grounding or power wiring problem that affects both.

The TPS signal goes directly to the ECM as an input.
That same TPS signal goes to the TPS buffer/amplifier. That TPS buffer/amplifier is a driver to prevent the ASR/ABS unit from loading down the TPS signal.
The output of the TPS buffer/amplifier goes directly to the ASR/ABS unit without going over the serial link.

Tom Piper

 

The CCM is the master computer, it controls the communications on the serial-link.
The ECM, ASR/ABS, and C68 climate control units are all slaves.
However, the ECM can run the vehicle standalone after the engine is started.

The CCM requests information (vehicle speed, engine rpm, etc. but, NOT TPS) from the ECM to send to the ASR/ABS and C68 computers.
If the CCM does not get that information after several requests, the CCM considers the serial-link to be at fault.

Tom Piper

 

The TPS error, is it more like to be the TPB buffer or the TPS itself?

Again, thanks!

 

One thing to keep in mind, anytime you replace the throttle body, throttle position sensor, or TPS buffer, you should locate a Vetronix Tech-1A, or MasterTech scan-tool (an expensive scan-tool) with the chassis cartridge and do a "TPS Learn" procedure -- this is in the shop manual.
This causes the ASR to learn the settings of the TPS system so ASR functions correctly when relaxing the throttle. But, that is all it affects.
If ASR isn't important to you, then don't worry about it.

Since your original post mentions the TPS error in relation to the ASR unit, logic would seem to indicate it was the buffer.
However, the TPS signal is the input to the buffer: garbage in = garbage out.
So, if the TPS was faulty, the faulty signal would be passed through the buffer and sent to the ASR.
Conventional wisdom would seem to dictate that, if the throttle position sensor signal were faulty, the ECM would probably set an error code for the TPS too.

If you have a cheap scan-tool for the ECM, you probably can monitor the TPS signal from the ALDL connector under the dash -- or you could use a good voltmeter connected directly to the TPS wiring.
Just move the throttle position SMOOTHLY through the entire range of travel. The output of the TPS should be a SMOOTH transistion with no spikes.

All that being said, it seems you have several problems.
Either they are individual problems or you must have ground or power wiring problems.

Tom Piper

 

I did clean the throttle body awhile back, so I think I will try resetting the TPS first.