tcen24b

I have a 1999 C5 that has numerous codes one being p1518.I tried clearing the codes and the p1518 will clear but comes right back up.So this does not allow me to manually advance through the rest of the codes to clear them. The car showed all the service warnings and went into reduced power and died. It will not start. I read the my dash has gone nuts thread and performed all the task listed. I was going to clear all the codes and crank the car and see which ones came back up but as I said the car will not start. Any help will be greatly appreciated. Tommy

SS2001SS

Don't know much about it but here's some info to get you started:
https://www.corvetteforum.com/forums...post1567417358

dadaroo

What dies no "start" mean? Does the starter seem to crank the engine?

tcen24b

Yes the starter spins the engine it just won't start.

dadaroo

Have you measured the battery voltage AT the battery? The car will crank on low volts but the electronics will go nuts.

A fully charged battery should be 12.6v or more.

It's not 12 volts it's 12.6 because each cell is 2.1 volts.

If the battery is

12.5 = 85% charged
12.4 = 65%
12.3 = 50%
12.2 = 35%
12.1 = drained

tcen24b

Yes I did , replaced it yesterday.The new one has correct voltage.

dadaroo

Try to go thru the codes again to see if any others show up. Don't try to delete P1518 when you do it.

Never heard of not being able to look thru codes because of one code locking the DIC up.

tcen24b

O.k. I will try that.

The DIC will scroll through the other codes until I go manual. It returns to the p1518 and will not scroll forward or backward.

madmatt9471

Here is a little extra help for you:

P1518 Chevrolet

P1518 Chevrolet - Throttle Actuator Control Module Performance

PDF Share Code 2 P1518 Chevrolet Comments | Add Comment
Possible causes
- Dead or weak battery
- Faulty Throttle Actuator Control (TAC) module
- Throttle Actuator Control (TAC) module harness is ope or shorted
- Throttle Actuator Control (TAC) module circuit poor electrical connection
- Check Throttle Actuator Control (TAC) module connector for water

What does this mean? What does this mean?
When is the code detected?

The Engine Control Module (ECM) has detected a loss of data or invalid data from the Throttle Actuator Control (TAC)
Possible symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- No throttle response

P1518 Chevrolet Description
The Throttle Actuator Control (TAC) module contains data which is essential for proper TAC operation. The TAC module continuously test the integrity of this data. When the TAC module is unable to write or read data to and from random access memory (RAM), or the TAC module is unable to correctly read data from the flash memory or and internal TAC module processor fault is detected and the Detected Trouble Code (DTC) is set.

You are going to have to look at your connection on your TAC module located next to the PCM in the passenger fender well (thru access panel)

It is very very possible that battery acid has leaked down and got on the connections of the TAC module - this is the module that communicates between the throttle (gas pedal), PCM, and Throttle Position Sensor (side of the Throttle Body)

Inspect all of those! Especially under the battery, passenger side fender well access panel!

Thanks,Matt

madmatt9471

Tommy,

Also check all your grounds on the Vette, here is a member who has recently done this - with many pictures

https://www.corvetteforum.com/forums...re-report.html

Thanks,Matt

tcen24b

I will do that now.

madmatt9471

Right on!

I gotta leave soon but I will check in on my phone from time to time!

Thanks,Matt

tcen24b

There was no acid in or on these components just some dirt. I have to stop for today.thank you.

madmatt9471

Ok.

You still want to uncle it and check the connections and check all your grounds. Plus it just might be that the TAC module crapped out on you.

If you have a friend that would allow you to try his that might help some too.

I have more ideas that will help.

Thanks, Matt

tcen24b

A little more info; I was driving the car when the dash went nuts and the car died. These are the codes I originally got off the DIC
10pcm-p1518 hc bo-rfa u1255 h 58sdm u1301h
28tcs- c1276 hc u1096 h 28tcs c1276 hc
c1278 h u1064 h c1278 h
ao ldcm b2252 h u1016 h
b2282 h ai rdcm b2253 h 99 hvac b03161 h
b2284 h b2283 h b0363 hc
b2264 h b2285 h b0441 hc
u1255 h b2265 h
u1064 h u1253 h
u1016 h u1064 h
u1096 h u1016 h
u1096 h

I'm going to check connections on the TAC.

jodyjo

The only time I've had my dash go nuts, throw all of those codes and more, and put me In reduced engine power and what not was because of a weak battery.

madmatt9471

It looks like there is a lot of Loss of Communication or GROUND codes there - these could be from the removal of the battery too - but more than likely there is a connectivity issue!

You will need to check the TAC module for (1) Proper Connection (2) Moisture (3) Corrosion of any sort

You will want to check "ALL" of your grounds and connection points - especially the one next to the Battery Compartment on the top of the frame too - (between the battery box and exhaust manifold top of the frame, these can be knocked off or broken)
https://www.corvetteforum.com/forums/...re-report.html

Plus when down by the TAC make sure the PCM ground wire is there or may even run an additional one to it, its body etc.

Have you cleared all the codes?

Which ones do come back?

Thanks,Matt

madmatt9471

Loss of Communication codes are:

1016
1064
1096

Thanks,Matt

madmatt9471

C5 Corveete Codes:
http://www.stengel.net/diccodes.htm

10pcm-

p1518 hc - PCM to TAC Module Serial Data Circuit

bo-rfa - (Ex. Tire pressure sensors)

u1255 h - Serial Data Line Malfunction

58 sdm

u1301h - Class 2 Circuit Shorted to Battery (Only found this number under TCS List)

28tcs-

u1096 h - U1096 Loss of Communications with IPC (Under BCM)
c1276 hc - Delivered Torque Signal CKT Malfunction
c1278 h - TCS Temporarily Inhibited By PCM
u1064 h - U1064 Loss of Communications with BCM (Under IPC)

ao ldcm

b2252 h - Key Cylinder Switch Fault
u1016 h - Loss of Communications with PCM
b2282 h - Battery #1 Fault

ai rdcm

b2253 h - Key Cylinder Switch Fault

99 hvac

b03161 h - B0361 Left Actuator Feedback Short to GND
b2284 h - B2284 Battery #2 Fault (Under LDCM)
b2283 h - B2283 Battery #1 Fault (Under RDCM)
b0363 hc - Left Actuator Feedback Open (HVAC)
b2264 h - B2264 Vertical Position Sensor Fault (Under LDCM)
b2265 h - Horizontal Position Sensor Fault (Under LDCM)
b2285 h - B2285 Battery #2 Fault (Under RDCM)
b0441 hc - B0441 Left Actuator Out of Range (HVAC)
u1253 h - ?
u1255 h - U1255 Serial Data Line Malfunction
u1064 h - U1064 Loss of Communications with BCM
u1016 h - U1016 Loss of Communications with PCM
u1096 h - U1096 Loss of Communications with IPC

Some of these are outta whack in their order (I tried to use your list to the best I could)

You will want to check your (1) Ignition Switch (2) Both doors to make sure they have "NO" pinched wires in the accordion (3) Your BCM for moisture (4) You are going to have to read through this post https://www.corvetteforum.com/forums...tion-long.html which has about every problem electrical in it, including yours. Even the Ignition Switch and BCM etc.

It definitely sounds like something is related throughout, something common.

Have you done anything else to the Vette recently?

List all that you have done to it recently and in the recent past!!!!

Thanks,Matt

madmatt9471

What was the cause of yours?

This definitely can help!

Thanks,Matt