P0C17 and P0C18 Tahoe Hybrid 2008 - Page 2 - GreenHybrid - Hybrid Cars

P0C17 and P0C18 Tahoe Hybrid 2008

  #11  
Old 02-18-2019, 05:13 PM
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Default Re: P0C17 and P0C18 Tahoe Hybrid 2008

Originally Posted by SonomaGTLS6 View Post


Might be worth reseating all of the connectors. Strange to me that both position sensors would fail at the same time. If you can find pinouts for the connectors on the trans that might be a start for troubleshooting...make sure proper voltage is at the pins necessary. If they are sensor pins going back to the PCM or TCM, I’d assume they are fed by a 12V line.
I'm not sure that I understood everything correctly. But I checked all the fuses and relays. I also put a new 12v battery.
 
  #12  
Old 02-18-2019, 05:20 PM
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Default Re: P0C17 and P0C18 Tahoe Hybrid 2008

Originally Posted by Chicago38 View Post
I'm not sure that I understood everything correctly. But I checked all the fuses and relays. I also put a new 12v battery.
Thinking more that there is a voltage or ground supply issue to the transmission harness. Probably hard to check given the connection system is sealed but you could at least see if there is any corrosion or terminals dislodged after disconnecting the connectors.

Another thing you could do is check out the pins in the connector shown on page 5/6 here...looks like there’s some service info highlighting that terminals could be out of place. Maybe someone with access to inline connector or harness schematics for service information can get the pinouts for the trans connectors.

https://ww2-secure.justanswer.com/up...7_222501_1.pdf
 
  #13  
Old 02-28-2019, 09:08 PM
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Default Re: P0C17 and P0C18 Tahoe Hybrid 2008

Originally Posted by Jaime View Post
I recently purchased one of these VCXNano scantools that comes with a Windows version of a Tech2. This may let you initiate the Jump Assist mode. I would first verify that the battery really is discharged by reading the module voltages. If you already have an OBD2 scanner, look at the following post that shows you how to read the voltages:

https://www.greenhybrid.com/forums/f...results-31736/
​​​​I bought a scanner what you said and made a diagnosis that showed the charge of the hybrid 213v battery.I tried to clear the error codes but they are not deleted. I also tried to reprogram the modules but with this scanner it is impossible.
​​​​​​I also disconnected the connectors on the transmission trying to find bad contacts, but everything is in ok.
I do not even know it makes sense to remove the transmission pan and check the wiring harness inside?!
 

Last edited by Chicago38; 02-28-2019 at 09:13 PM.
  #14  
Old 02-28-2019, 11:06 PM
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Default Re: P0C17 and P0C18 Tahoe Hybrid 2008

A hybrid battery at 213V is completely dead. There are 240 cells. For a prismatic module to drop below 1V/cell, it's pretty much a death sentence. When the battery is EMPTY, but can still properly hold a charge, you will NOT see a voltage less than 288V. A battery with some usable charge that has sat for a year will still read greater than 296V.

I can only conclude the vehicle sat for so long, the already tired HV battery completely discharged.

There is NO way to reliably diagnose the vehicle with the HV battery in that state.
 
  #15  
Old 03-01-2019, 04:27 PM
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Default Re: P0C17 and P0C18 Tahoe Hybrid 2008

Still not sure of the background of the vehicle? Regardless of that, if your battery voltage check is correct then the source of your problem is most likely a completely dead Hybrid battery pack, not the $6,000.00 transmission. That is actually good news as a replacement battery is much cheaper than a transmission. If you are in the Chicago area you might give Mike a call over at Best Hybrid Batteries just outside of Chicago (800) 770-8832 . I recently bought a new hybrid battery from them and so far it is doing OK. I currently have the old hybrid battery pack on my workbench doing some testing while waiting to see how the new one performs over the next few weeks. The old battery appears to be badly deteriorated from my preliminary test results. Hoping to be complete all the data gathering by the end of this weekend. It takes about 3 hours per module to test so 3 x 40 modules equals 120 man hours. My time is worth around $400.00 per hour so I will have around a $48,000.00 investment when done LOL (enough to buy 12 brand new batteries, or actually a entire new car) No problem though as I am happy to donate my time to contribute to the GreenHybrid forum knowledge base. Success is dictated by the ability to do better than good enough.
 
  #16  
Old 03-03-2019, 05:53 PM
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Default Re: P0C17 and P0C18 Tahoe Hybrid 2008

Purchase:

LPC-100-350
APC-35-350
400V+ 1A diode/rectifier

Install the diode in the (+) output lead of the LPC-100-350
Wire the LPC input to a suitable AC cord.

Remove the safety plug.
Open the battery.
Attach the DC out leads of the LPC-100-350 to the relays on the battery side.
Energize the LPC
Install the safety plug.
Charge until pack is at or near 286V
Remove the safety plug
De-energize the LPC
remove the (-) lead from the relay.
Wire the APC-35-350 output in series with the LPC, (-) to relay, (+) to (-) of LPC.
Wire their inputs in parallel.
Energize both supplies.
Install safety plug
Charge for the sooner of 6 hours or until the pack has warmed to the touch.
Remove safety plug
De-energize power supplies
Detach power supplies from battery.
Close battery
Install safety plug

Disconnect 12V for 2 minutes
Reconnect 12V

Profit
 
  #17  
Old 03-03-2019, 08:26 PM
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Default Re: P0C17 and P0C18 Tahoe Hybrid 2008

Originally Posted by S Keith View Post
Purchase:

LPC-100-350
APC-35-350
400V+ 1A diode/rectifier

Install the diode in the (+) output lead of the LPC-100-350
Wire the LPC input to a suitable AC cord.

Remove the safety plug.
Open the battery.
Attach the DC out leads of the LPC-100-350 to the relays on the battery side.
Energize the LPC
Install the safety plug.
Charge until pack is at or near 286V
Remove the safety plug
De-energize the LPC
remove the (-) lead from the relay.
Wire the APC-35-350 output in series with the LPC, (-) to relay, (+) to (-) of LPC.
Wire their inputs in parallel.
Energize both supplies.
Install safety plug
Charge for the sooner of 6 hours or until the pack has warmed to the touch.
Remove safety plug
De-energize power supplies
Detach power supplies from battery.
Close battery
Install safety plug

Disconnect 12V for 2 minutes
Reconnect 12V

Profit
Thanks for this instruction, it looks very serious. I'm not sure that I understood every step, but I have a question Jump Assist mode do the same thing but on the factory settings?
 
  #18  
Old 03-03-2019, 10:09 PM
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Default Re: P0C17 and P0C18 Tahoe Hybrid 2008

No. According to this, jump assist won't work if the hybrid battery is less than 240V:

https://f01.justanswer.com/Bluegoril...ocument-10.pdf

The likelihood of your battery being salvageable is essentially zero, but it's probably worth $50 worth of power supplies and 8 hours (2 hr install, 6 hr charge) of your time to find out.
 
  #19  
Old 03-03-2019, 10:12 PM
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Default Re: P0C17 and P0C18 Tahoe Hybrid 2008

Originally Posted by Jaime View Post
Same purpose. To charge the battery. The Jump Assist mode is not recommended to be done for more than 30 minutes, but with S Keith's instructions you can fully charge the battery.
Yes, but one shouldn't. Charging at such a low rate is generally safe, but active cooling is required. Sadly the prescribed 6 hours may fully charge the battery, but the goal is to get a minimum (6 * 350)/6500 = 32% SoC.
 
  #20  
Old 03-13-2019, 04:28 PM
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Default Re: P0C17 and P0C18 Tahoe Hybrid 2008

In the instructions for jump assist there are mentions of high voltage contactor relays, you need to compare two battery readings and if the difference is more than 30 volts, it means that high voltage contactor ralays is not closed. Who can say something about this relay?
Because it shows completely different values when I check.
 

Last edited by Chicago38; 03-13-2019 at 04:33 PM.

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