I have a 99 4wd auto, bone stock. The tranny doesn't want to shift out of first. I have replaced the output shaft speed sensor, the governor pressure sensor and transducer. I also replaced the ecm due to the delayed WTS light/fuel pump issue. I checked my alternator for AC noise using a snap on meter it it was 0.03 to 0.05. I've owned the truck for 4 months and it appears to have a fairly new alternator. I took the truck to a local tranny shop (long time biz) he hooked it up to a snap on solus scanner and we drove the truck for about 20 minutes. During that time he said the computer had the p1693 and he couldn't communicate with the body control module. My door chimes, power locks etc work...He then said he felt the PCM may be bad and suggested I borrow one from a friend to see. Problem is, I have the only auto...

Can you tell me where the body control module is and what your thoughts are on it..

I appreciate your time

Mike

Western KY

So don;t go throwing money at it yet.

 

p1693 is compainion code meaning that there is a code in the system but you need to get a code scanner to read it.  Go to the local parts store and ask to borrow one.   Read the codes and report back.

So far I have used a matco tools scanner. A snap on solus scanner and a different larger in size snap on scanner to attempt to read the codes and all I or anyone can find is the p1693 with no communication with the body control module..

1693 is a code in another module. Which means there are more codes. Did you adjust the bands?

I have not actually adjusted the bands. When I put the new transducer and sensor in I did look at them and they wasn't a bunch of slack in the front or rear bands. That being said, no I haven't put my torque wrench on them yet. Another thing is I can take the negative battery terminals off for about 10 minutes, put them back on and it will shift perfect for about 2 minutes.

You got something putting you into limp mode. Bands need to be adjusted but probably wont be the problem

Ok thanks for the fast replies. I will keep working on it .

That 1693 really just means there is another code in the system. I would try to track down that other code and see where that leads you. I am betting its related to your problem.

Couldn't agree more.

Ok I will check on it tomorrow and report back. Thanks again

One of the symptoms of a bad ecm/pcm is not being able to connect to it with a scanner (no communication error). I went through the same issue, started experiencing odd/no shift patterns so I took it to a known and trusted trans repair shop and he couldn't even connect to the truck with his snap on scanner. After eliminating a few other possibilities he came to the conclusion my pcm was toast. I was a little skeptical but he told me he would keep the pcm if it didn't resolve my issues so I let him do the work, and the new pcm fixed it.

Where are you located? You may be near somebody that could either help out or know of a reputable shop you could reach out to for some advice.

Limp mode will keep it in 3rd gear not 1st.

 

Pcm is a possibility or a stuck TV cable will do it too. If it is stroked into full throttle position is will stick in first gear too.

 

I had a BD torc lock on my 02 and the vacuum cylinder would get dry and stick at full pressure some times and it would not shift out of first, I would have to stomp the go pedal all the way down to get it to release and then knew it was time for some lube. It would shift from 1st at about 2500-2800 rpms if you ran it up that high but it was a hard shift and usually resulted in  .

The body control module is located between the ashtray and the cover below the steering wheel. It is also referred to as the CTM (central timer module) the key difference is do you have radio controls on the back side of the steering wheel? As for the shifting of the Trans. Take a volt meter and measure the voltage between the negative terminal and the cable on your battery.

I don't have radio control on the steering wheel. When in get home I will check the battery voltage. Thanks

I currently have a 99 QCLB that I recently swapped an NV5600 from a 2001 QCSB. I swapped everything excluding PCM or ECM. I even swapped PCM harnesses. My issue is that I lost cruise control in the process. If someone has a manual PCM for a 99, I can let go of mine for a whatever the manual PCM costs. Maybe we can help each other. My truck drives perfect otherwise.

I currently have a 99 QCLB that I recently swapped an NV5600 from a 2001 QCSB. I swapped everything excluding PCM or ECM. I even swapped PCM harnesses. My issue is that I lost cruise control in the process. If someone has a manual PCM for a 99, I can let go of mine for a whatever the manual PCM costs. Maybe we can help each other. My truck drives perfect otherwise.

I think you can just have your PCM reprogrammed for your VIN number. I have heard of places online that will do it or maybe the dealership would do it for ya?

If you can find any shop that has the DB3 they can update the body control module.

Ilikeoldfords: I still have my original PCM. I kust swapped the harness from the manual truck so he could have the auto plugs needed for transmission. I think the manual harness is wired a bit different than the auto trans harness since I lost cruise control. Everything else works with no issues. I have full engine power, etc... I think a manual PCM is required, unless someone knows how it needs to be wired.

Im sure the auto pcm and manual pcm are different as far as cruise. If you think about it, the pcm controls the cruise and needs to know when to cancel the cruise. It has to watch the clutch pedal sensor, brake pedal, and switches.

Here is the computer layout...