Chevy Sonic - P0599 Thermostat Heater Control Circuit High
video description
Date: 2020-08-05
Related videos
Comments and reviews: 7
Duc
I would not have figured this one out without you and this video. On my 2015 Sonic 1. 8, I had a P0599 but I could not get the test light to light up. I went through and tested with a pigtail socket and bulb and was trying to command it with my Launch Mini ProS and it showed the same malfunction but I could not get the bulb to light which was a fairly large 921 bulb.
I went to the wiring diagram and checked the ground wire from the ecm to the thermostat for resistance and then load tested it as well and it tested good. I also tested the power wire with the test light from the power side of the circuit to the negative on the battery and it was good also. Once you mentioned the resistance values, I checked the resistance of that bulb and it was 2. 5ohms and the thermostat was at 1. 5ohm so I replaced the 921 with a 194 mini bulb that had a resistance of about 5 ohms, the test then worked like yours in the video and the malfunction on the scan tool went away and ended up being just a bad thermostat as well. You tested the new oem part and it showed 15 ohms so somewhere between 2. 5 and 5ohms is the limit in the ecm resistance check on that circuit.
I installed a new thermostat and all is good! Thanks, Eric.
reply
I would not have figured this one out without you and this video. On my 2015 Sonic 1. 8, I had a P0599 but I could not get the test light to light up. I went through and tested with a pigtail socket and bulb and was trying to command it with my Launch Mini ProS and it showed the same malfunction but I could not get the bulb to light which was a fairly large 921 bulb.
I went to the wiring diagram and checked the ground wire from the ecm to the thermostat for resistance and then load tested it as well and it tested good. I also tested the power wire with the test light from the power side of the circuit to the negative on the battery and it was good also. Once you mentioned the resistance values, I checked the resistance of that bulb and it was 2. 5ohms and the thermostat was at 1. 5ohm so I replaced the 921 with a 194 mini bulb that had a resistance of about 5 ohms, the test then worked like yours in the video and the malfunction on the scan tool went away and ended up being just a bad thermostat as well. You tested the new oem part and it showed 15 ohms so somewhere between 2. 5 and 5ohms is the limit in the ecm resistance check on that circuit.
I installed a new thermostat and all is good! Thanks, Eric.
reply
Garth
Amazing technology, make the engine run hot even though it isn't working hard. Most of this emission device mumbo jumbo actually destroys the vehicle to meet the exhaust pipe testing. Many say the diesel trucks with the the DPF? DEF systems do exactly the opposite operations a healthy engine should do. They run them artificially hot, squirt raw fuel into the cylinders to regen killing MPG and turbos, create added maintenance and costs to the owner and cause early engine failure of about one half. They say some of the Fords will fail in 100, 000 miles requiring a complete engine crate or 20, 000 in costs plus, maintenance or replacement of the DEF filter (usually the cause for extreme back pressure as it ages. The EPA sure knows how to make personal property become public property very fast.
In this matter, a good mechanic just saved the customer hundreds of dollars for an ECM that would not have repaired the problem! More auto manufacturer expense passed onto the car owner which is needless engineering.
reply
Amazing technology, make the engine run hot even though it isn't working hard. Most of this emission device mumbo jumbo actually destroys the vehicle to meet the exhaust pipe testing. Many say the diesel trucks with the the DPF? DEF systems do exactly the opposite operations a healthy engine should do. They run them artificially hot, squirt raw fuel into the cylinders to regen killing MPG and turbos, create added maintenance and costs to the owner and cause early engine failure of about one half. They say some of the Fords will fail in 100, 000 miles requiring a complete engine crate or 20, 000 in costs plus, maintenance or replacement of the DEF filter (usually the cause for extreme back pressure as it ages. The EPA sure knows how to make personal property become public property very fast.
In this matter, a good mechanic just saved the customer hundreds of dollars for an ECM that would not have repaired the problem! More auto manufacturer expense passed onto the car owner which is needless engineering.
reply
Duncan
Leave it to auto engineers to take something as simple as a thermostat and complicate the hell out of it! Just when I thought I'd heard it all. yeah right! What is the sense in that feature? I'd really like to know the answer to that question. I just can't wrap my head around an electronically heated thermostat in a car. It's nuts! Thanks for the video. There's more money in ECM's than there are in thermostats.
reply
Leave it to auto engineers to take something as simple as a thermostat and complicate the hell out of it! Just when I thought I'd heard it all. yeah right! What is the sense in that feature? I'd really like to know the answer to that question. I just can't wrap my head around an electronically heated thermostat in a car. It's nuts! Thanks for the video. There's more money in ECM's than there are in thermostats.
reply
Mark
Just seen this video like 3 years to late. I work for Vauxhall in the UK. We have this engine and the 1. 6 variant in most of our models and we change theses thermostats every week. You can just get the front half of the thermostat on its own without all the housing on the back. Much easier and quicker. They are crap design. Anyway love the videos whilst on lockdown. Cheers Dr O.
reply
Just seen this video like 3 years to late. I work for Vauxhall in the UK. We have this engine and the 1. 6 variant in most of our models and we change theses thermostats every week. You can just get the front half of the thermostat on its own without all the housing on the back. Much easier and quicker. They are crap design. Anyway love the videos whilst on lockdown. Cheers Dr O.
reply
Theramsey3
Biggest problem you had with that particular flow chart, is you didn't follow the instruction, where it said the light should have been off it also said the key should have been off. The last line on the page told you to replace the thermostat. If you had followed the instruction you still would have replaced the thermostat not the ecm.
reply
Biggest problem you had with that particular flow chart, is you didn't follow the instruction, where it said the light should have been off it also said the key should have been off. The last line on the page told you to replace the thermostat. If you had followed the instruction you still would have replaced the thermostat not the ecm.
reply
horseshoe
Thank you for posting this video. My sister's Cruze was giving the same code with the same engine. I will be test the resistance of that heater tonight.
I've also found just the thermostat and gooseneck, with heater by Stant. In all actuality, it wouldn't surprise me if Stant makes the OE.
reply
Thank you for posting this video. My sister's Cruze was giving the same code with the same engine. I will be test the resistance of that heater tonight.
I've also found just the thermostat and gooseneck, with heater by Stant. In all actuality, it wouldn't surprise me if Stant makes the OE.
reply
eckoecho
I replaced the thermostat and the housing and the check engine light came back on with the same code (even after disconnecting the + side of the battery to clear the code) I never see it leaking coolant but its always running low. Any thoughts on what it could be?
reply
I replaced the thermostat and the housing and the check engine light came back on with the same code (even after disconnecting the + side of the battery to clear the code) I never see it leaking coolant but its always running low. Any thoughts on what it could be?
reply
Add a review, comment
Other channel videos
