Will not fully seated Memory Clibration module always...

[Schrade]

... light up more than 1 DTC code?

I got a 42 4 module H. I cleared it, started diags running for a couple minutes, and it didn't light up again (I hate problems that go away by themselves).

FSM says first 'Intermittent' is to check MEM-Cal module for seating.

If it's not seated, won't it cause ALWAYS at least SEVERAL DTC's, instead of just one??

[XfireZ51]

If you put it into DIAG mode, it should just give you 1 + 2 flashes, 3 times, then repeat. Have you looked at the prom? The blue and white levers on each end should be locked in. Is your MALF code for the ECM or CCM?

[Schrade]

Haven't started digging yet there Darryl; waiting to see if the code lights up again here...

Diagnostic mode LCD showed proper when reading, and when cleared.

Loose ground somewhere probably - haven't checked any system ground connections either. LCD flickers occasionally too.

Still trying to de-compile the automatic install, and get it zipped up.

[XfireZ51]

Sounds like a CCM issue

[Schrade]

Sounds like a CCM issue

Funny that you say that there Sir; also saw when I bought it last year, a module 1 CCM H72, which I believe is voltage deviation...........

32k car shouldn't have grounds problem otherwise.

Corrosion in some grounds I'm sure; previous owner had the headlight motor short, which was draining the battery. He also had mounted an onboard trickle charger for this. Fumes HAD to be involved.

[XfireZ51]

Those are CCM codes, not ECM.

[Schrade]

Those are CCM codes, not ECM.

The module 4 H42 is ECM I think...

[XfireZ51]

The module 4 H42 is ECM I think...

You don't read ECM codes on the speedo display. You read them by counting the flashes of the SES light on the DIC.

[Schrade]

You don't read ECM codes on the speedo display. You read them by counting the flashes of the SES light on the DIC.


That's how my '87 was, but this one ('90) isn't flashing???


ed.:
OK - I'm thoroughly confused now.

So I plugged in the clip again. Am I puttin' tunnel vision on the LCD, and missing the SES flash? Nope.

I'm lost.


2nd ed.:
My '90 FSM says module 4 is for ECM.
And it's displaying in the LCD???

[Schrade]

That's how my '87 was, but this one ('90) isn't flashing???


ed.:
OK - I'm thoroughly confused now.

So I plugged in the clip again. Am I puttin' tunnel vision on the LCD, and missing the SES flash? Nope.

I'm lost.


2nd ed.:
My '90 FSM says module 4 is for ECM.
And it's displaying in the LCD???

bumpin' this one here...

Am I missing something here with Z package?

Is diagnostic readout different from base model L98 / LT1?

[-=Jeff=-]

Let's start from the beginning.. Tell us exactly how you are grabbing the codes.. Are you installing a jumper somewhere or?

[Schrade]

Yes - jumper into the sockets 'A' and 'G'...

http://www.justanswer.com/uploads/flexfuel702/2008-06-27_181656_obd1pinout2.gif

[WVZR-1]

You don't read ECM codes on the speedo display. You read them by counting the flashes of the SES light on the DIC.

The OP is correct - Module 4 in the LCD display is ECM fault codes. You can't do "HISTORY" from the SES/CEL only a present code is flashed when requested.

OP - The H72 is a CCM code and most frequently accompanies a replacement of the radio head with something from the after-market. There's diode and resistor replacements that accomplish a patch for those. I would imagine there's many other issues that could set the 72.

In your original post you mention the H42 and that you cleared it. The H (HISTORY) is just a reference that it has been recorded and would remain until "cleared". Once cleared you won't see that HXX whatever it might be I wouldn't think until it were set again and then it would just be the CXX, C (CURRENT) code until the repair made and then would become HXX again in the module 4 diagnostics until cleared there again.

Any CXX codes in module 4 I would think should be actively displayed with the SES/CEL light "ON".

[-=Jeff=-]

for the SES to Flash I believe it is A & B that are jumpered

for the FX3 it is A & C

doing what you are doing is just like what WVZR-1 is saying, the H codes are history ones and not current

[Schrade]

The OP is correct - Module 4 in the LCD display is ECM fault codes. You can't do "HISTORY" from the SES/CEL only a present code is flashed when requested.

OP - The H72 is a CCM code and most frequently accompanies a replacement of the radio head with something from the after-market. There's diode and resistor replacements that accomplish a patch for those. I would imagine there's many other issues that could set the 72.

In your original post you mention the H42 and that you cleared it. The H (HISTORY) is just a reference that it has been recorded and would remain until "cleared". Once cleared you won't see that HXX whatever it might be I wouldn't think until it were set again and then it would just be the CXX, C (CURRENT) code until the repair made and then would become HXX again in the module 4 diagnostics until cleared there again.

Any CXX codes in module 4 I would think should be actively displayed with the SES/CEL light "ON".

Correct? REALLY :eek: ? I ain't used to that - except in my own castle of course. :mrgreen:

Thanks there Dave - makes sense - I'm getting feedback still in the radio, in PERFECT sync with the TPS, and it's because of the TCI EZ-GO TCU for the auto. :mad: - speed shop is dragging their feet on that still.

The ECM 42 has not re-curred. Now it's an ECM H 61 - also attributable to the auto mod, I'm presuming...