04-18-2024, 05:49 AM | #1 |
Drives: 2017 2SS Convertible Join Date: Mar 2021
Location: Warsaw, Poland, EU
Posts: 95
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A8 TCM module removal - is car still driveable?
Hello,
I have a situation where I want to remove a TCM from SS with A8 in order to unlock it and be able to minimize the shudder (by changing lock-up speed delta) however in the meantime I need to leave the car in at the shop to fix some body work issues. Question can a car without TCM move around the parking lot at mechanic's (in an emergency or service mode)? I have info that the older transmissions were able to work without TCM just allowing you using 3rd gear and reverse. Is that the case for A8? I will appreciate a feedback. BR, Jarek
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Camaro SS 2017 Convertible, 2SS trim, V8 6.2L 455HP 618Nm, A8, Silver
Mods so far: K&N oil air filter, rear lamps EU conversion with sequential turn signal, exhaust modification to 4 tips (non-NPP), LED rear fog light (EU requirement), side-markers conversion to LED Mods planned: Morimoto LED lamps set (front) |
04-18-2024, 09:04 AM | #2 |
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I just paid the extra money to buy the unlocked TCM from HPTuners because my car was my daily and could not have it down for a week waiting on the TCM to be unlocked. I don't think if it does not communicate with the TCM that it will move or even start? I could be wrong. I paid $400 for the TCM unlocked and programmed from HPTuners. But you have to copy some of the calibration files from the stock TCM and put them on the new one.
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04-18-2024, 09:39 AM | #3 |
Drives: 2017 2SS Convertible Join Date: Mar 2021
Location: Warsaw, Poland, EU
Posts: 95
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Thank you dmcmahan60.
In my case (as I am based in EU) I am actually travelling to US with my TCM to send it to HPTuners (to avoid any customs/taxation discussions and delay) so my options are limited. Like I have said in my 1st message - my mechanic told me that old transmission were able to go in emergency/service mode. I am curious if anybody had a similar situation.
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Camaro SS 2017 Convertible, 2SS trim, V8 6.2L 455HP 618Nm, A8, Silver
Mods so far: K&N oil air filter, rear lamps EU conversion with sequential turn signal, exhaust modification to 4 tips (non-NPP), LED rear fog light (EU requirement), side-markers conversion to LED Mods planned: Morimoto LED lamps set (front) |
04-18-2024, 02:00 PM | #4 |
Drives: 2016 Camaro SS 2017 Yukon Denali Join Date: Jan 2020
Location: Colorado
Posts: 116
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The a8 will not function without the tcm, similar to how the engine will not run without the ecm.
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04-19-2024, 02:45 AM | #5 |
Drives: 2017 2SS Convertible Join Date: Mar 2021
Location: Warsaw, Poland, EU
Posts: 95
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Thank you Efi69Cam.
Again was that tested or is just assumed? Sorry to be a bit harsh but looking for hard data.
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Camaro SS 2017 Convertible, 2SS trim, V8 6.2L 455HP 618Nm, A8, Silver
Mods so far: K&N oil air filter, rear lamps EU conversion with sequential turn signal, exhaust modification to 4 tips (non-NPP), LED rear fog light (EU requirement), side-markers conversion to LED Mods planned: Morimoto LED lamps set (front) Last edited by Jarek; 04-19-2024 at 04:34 AM. |
04-19-2024, 05:12 AM | #6 |
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I am pretty confident in saying that if the TCM is not there it will not start just like if there was no ECM it would not start.
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04-19-2024, 06:14 AM | #7 |
Drives: 2017 2SS Convertible Join Date: Mar 2021
Location: Warsaw, Poland, EU
Posts: 95
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Thank you dmcmahan60.
In that case I will need to test that.
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Camaro SS 2017 Convertible, 2SS trim, V8 6.2L 455HP 618Nm, A8, Silver
Mods so far: K&N oil air filter, rear lamps EU conversion with sequential turn signal, exhaust modification to 4 tips (non-NPP), LED rear fog light (EU requirement), side-markers conversion to LED Mods planned: Morimoto LED lamps set (front) |
04-19-2024, 10:28 AM | #8 |
Drives: 2016 Camaro SS 2017 Yukon Denali Join Date: Jan 2020
Location: Colorado
Posts: 116
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I don’t need to unplug my tcm to “prove” to myself the fact that an entirely electronically controlled device will not function without its controller.
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04-19-2024, 11:05 AM | #9 | |
Drives: 2017 2SS, 50th pkg, M6, MRC, NPP Join Date: Jan 2016
Location: Ocean City, NJ
Posts: 3,190
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Quote:
From what I have read some cars will default to 3rd gear and limp mode when the ECM loses communication with the TCM. EDIT: My above idea applies to a "lost communication" problem. Based on what I see in the repair manual, I think Efi is correct. The transmission needs the TCM connected to enter into its default modes. You can't remove the TCM completely. Below are the default modes, which all seem to show the TCM taking action: DIAGNOSTIC INFORMATION AND PROCEDURES > DTC P0601-P0604, P0606, P062F, P16F3, P16F4, OR P16FB: CONTROL MODULE > ACTION TAKEN WHEN THE DTC SETS P0601, P0603, P0604, P0606, P062F, P16F3 or P16FB P0601, P0603, P0604, P0606, P062F, P16F3 and P16FB are Type A DTCs. TCM turns Off power to all shift and pressure control solenoids. TCC is disabled. 2nd gear is obtained if fault was detected with the default valve in the low state. 8th gear is obtained if fault was detected with the default valve in the high state. TCM disables transmission adapts learning and freezes current adapt values. TCM inhibits Tap Up/Tap Down. TCM inhibits TCC. TCM requests the ECM to disable powertrain braking. TCM commands maximum line pressure for all shifts TCM request the ECM to limit engine torque based on transmission input speed. TCM request the ECM to disable neutral idle. TCM requests the ECM to disable auto grade braking. TCM request the ECM to disable auto stop function. P0602 or P16F4 P0602 and P16F4 are Type A DTCs. No other default action taken. Last edited by ctrlz; 04-19-2024 at 11:33 AM. |
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04-19-2024, 02:34 PM | #10 | |
Drives: 2016 Camaro SS 2017 Yukon Denali Join Date: Jan 2020
Location: Colorado
Posts: 116
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Quote:
The solenoids that control the hydraulics in the trans obviously cannot do anything without control by the tcm. I don’t have the service info in front of me but my instincts tell me that the default/no control state of the transmission is essentially neutral. |
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04-20-2024, 05:10 AM | #11 |
Drives: 2017 2SS Convertible Join Date: Mar 2021
Location: Warsaw, Poland, EU
Posts: 95
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Thank you ctrlz, Efi69Cam.
That's the answer I needed - hard facts.
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Camaro SS 2017 Convertible, 2SS trim, V8 6.2L 455HP 618Nm, A8, Silver
Mods so far: K&N oil air filter, rear lamps EU conversion with sequential turn signal, exhaust modification to 4 tips (non-NPP), LED rear fog light (EU requirement), side-markers conversion to LED Mods planned: Morimoto LED lamps set (front) |
04-20-2024, 05:35 AM | #12 |
Drives: People crazy with my sexiness Join Date: Jun 2023
Location: Northeast Ohio
Posts: 532
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Throw a two speed power glide in that baby and throw the TCM in the trash
I kid of course
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Purchase order submitted on 6/23/23
Received and purchased 9/8/2023 2024 2SS 6MT coupe Sharkskin/Light gray Moonroof/Navi/NPP/Mag Ride/Red Brake Calipers Gray painted split spoke wheels Illuminated footwells/illuminated bowtie |
04-22-2024, 10:02 PM | #13 |
Drives: Chevy camaro Join Date: Jan 2022
Location: Tennessee
Posts: 192
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Hire a couple of illegals to push it around the yard until you get the TCM back. Probably cheaper than a new unlocked TCM and the two of them can sleep in the back seat.
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Glenn
2017 Camaro 2LT RS Convertible |
04-23-2024, 05:02 AM | #14 |
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