Block heater cords on new Chevys

rondun1

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I was told by my dealer that my block heater cord only works under -18c. I would love to plug in around -10c. The dealer said if the cord is cut and a new end installed it will flag a code that will never come out. Anybody ever changed the end on there block heater cord?
 
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pipes

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Re: Block heater cores on new Chevys

I was told by my dealer that my block heater cord only works under -18c. I would love to plug in around -10c. The dealer said if the cord is cut and a new end installed it will flag a code that will never come out. Anybody ever changed the end on there block heater cord?

I heard the same thing but a friend of mine said that he had to change the end on his cord because it got damaged and said that he hasn't had any issues yet.
 

sirkdev

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Re: Block heater cores on new Chevys

I heard that as well and thought to myself if I want to plug my friggin truck in so its warm for a start so be it.... I hope its as easy as a cord end swap.
 

medler

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Re: Block heater cores on new Chevys

I asked a dealer on the cord to and they said don't do it. Will throw codes


Sent from my phone
 

mb1

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Re: Block heater cores on new Chevys

What about adding a oil pan heater.

Block heater on a duramax is 1500w I believe. I installed a 500w pan heater as well. Valve covers are warm on a -25 morning. I'd run the pan heater alone if I had to choose one. Warm oil and heat everything from the bottom up. Ideal IMO.


'12 T4
 

rondun1

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Re: Block heater cores on new Chevys

I never thought of an oil pan heater......I am going to ask my GM Dealer if it will flash a code.......thanks
 

Summiteer

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Re: Block heater cores on new Chevys

If the temp is what is causing the code, the pan heater would bring up the same issues, no?
 

slomo

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Re: Block heater cores on new Chevys

What it looks at is the ambient temp and compares it with the coolant temp up until -18 c the pan heater may set it off I will test it on a new one for you guys and see what the result is, but please don't cut the cords as this can cause several issues and they would not be covered under warranty . Such as in diesels insufficient regen, shut down of the def system, reduced engine power,
The ECM detects a temperature difference at power-up that indicates that the ECT sensor is 30°C (54°F) greater than the IAT sensor.
OR
The ECM detects a temperature difference at power-up that indicates that the ECT sensor is 10°C (18°F) greater than the IAT sensor, and the time spent cranking the engine is greater than 10 s, when the fuel level is greater than 5 %.
OR
With the power-up IAT more than −7°C (+19°F), the ECM detects a temperature difference at power-up that indicates that the ECT sensor is 20°C (36°F) greater than the IAT sensor. Then the vehicle must be driven for more than 6 min and 40 s at greater than 40 km/h (25 mph). If the IAT sensor then decreases greater than 4°C (7°F), an engine block heater was detected and the test is aborted. If the IAT sensor does not decrease, an engine block heater was not detected and DTC P0116 will set.
Action Taken When the DTC Sets
DTC P0116 is a Type B DTC.


Conditions for Clearing the MIL/DTC
DTC P0116 is a Type B DTC.


Diagnostic Aids
The use of non-thermostatically controlled aftermarket block heater will cause this DTC to set.
Inspect the ECT sensor terminals for corrosion and for engine coolant leaking through the sensor. Engine coolant that is leaking through the sensor will create a high resistance short to ground. This condition results in less voltage on the ECT sensor signal circuit, which is interpreted by the ECM as a warmer ECT.
An IAT sensor that is skewed colder at various ambient temperatures due to greater resistance than is normal will increase the range between these two sensors. Measure and record the resistance of the IAT sensor at various ambient temperatures, then compare those measurements to the Temperature vs Resistance table. Refer to Temperature Versus Resistance.
A slight to moderate resistance in the IAT sensor signal circuit or low reference circuit will increase the range between these two sensors. This condition results in a greater voltage on the IAT sensor signal circuit, which is interpreted by the ECM as a colder IAT.
 
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sirkdev

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Re: Block heater cores on new Chevys

I believe you are a gm tech so i believe what you are saying but why could a compromised block heater cord cause failed regens and def failure?
 

slomo

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Re: Block heater cores on new Chevys

It skews the ambient temp reading which is directly used by the def system and dpf which puts it in a inhibit mode we have had around 10 so far this year, was way worst when these cords first came out
 

whoDEANie

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Re: Block heater cores on new Chevys

Jebus, that's retarded. Thanks for the info SloMo.
 

crossfire879

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I snipped off the end of my cord on my '12 duramax to put a new one on and it works fine. No codes.

Sent from my SGH-I747M using Tapatalk
 

rondun1

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I think I will pray for spring to come......or warm weather....lol. I think I will just leave the cord the way it is. I will still look at all the input you guys send. Thank you.
 

brian h

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changed the cord end on a company truck and it never threw any codes and caused no problems. the problem with the oil pan heater is you need to plug it in when you first park your truck and keep the oil warm otherwise the pan heater starts to bake the oil that is against the pan before heating all the oil,ive seen this before whenever a person pulls a oil pan off the bottom of the pan is baked crude on it from the heater
 

OVERKILL 19

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changed the cord end on a company truck and it never threw any codes and caused no problems. the problem with the oil pan heater is you need to plug it in when you first park your truck and keep the oil warm otherwise the pan heater starts to bake the oil that is against the pan before heating all the oil,ive seen this before whenever a person pulls a oil pan off the bottom of the pan is baked crude on it from the heater

^^^^^yup!^^^^
 

OVERKILL 19

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Over time any oil breaks down and with being overheated when not flowing it will build up these deposits. Imo
 
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