Very persistant code 15

JTalley · Post by **JTalley** » Fri Mar 02, 2012 11:37 am

My coolant sensor broke a while back- the plug snapped off. When that happened, it flooded bad. I replaced it and it ran normal again. Now the CEL comes on randomly and it floods. I pulled the codes and got another 15, even though I reset them when I replaced the sensor. I know my O2 sensor is bad, but I can't replace it yet. Could that throw the code?

Post by **MountainManJoe** » Fri Mar 02, 2012 2:38 pm

Maybe the sensor plug wires broke too.

JTalley · Post by **JTalley** » Fri Mar 02, 2012 5:36 pm

The plug on the sensor is what broke. The plug from the wiring harness seemed to be fine.

Post by **MountainManJoe** » Fri Mar 02, 2012 9:03 pm

Short the sensor wire to ground, and turn on ignition. Gauge should register max temp. If not, wiring is faulty.

Check:
- fuses
- PCM connections

v8famvan · Post by **v8famvan** » Fri Mar 02, 2012 10:17 pm

Check the condition of the terminals in the connector to the temp sensor. If the terminals are corroded or spread, you may have poor or intermittent contact with the sensor resulting in an incorrect reading to the computer. If they are spread, you can tighten them up with a pin/needle. If they are corroded or in otherwise poor condition, replace the connector pigtail.

JTalley · Post by **JTalley** » Sat Mar 03, 2012 4:33 pm

Success!!! I messed around with that plug a bit, and the problem seems to be gone. Hopefully that fixed it.

Post by **MountainManJoe** » Sat Mar 03, 2012 4:53 pm

If you just jiggled it, then the problem is gonna come back. Next time you go to the junkyard, look for a newer GM vehicle and find another connector that's in good shape. It'll cost you pocket change and solve your problem permanently. Make sure the rubber seal is intact, and spread some dielectric or silicone grease over it so moisture doesn't get in.

JTalley · Post by **JTalley** » Sat Apr 28, 2012 8:01 pm

I've finally bought a new pigtail for it. How do I replace it? I heard that splicing it can make it get an improper reading, but I can't seem to find anything in my repair manual about putting a new connector on.

lockdoc · Post by **lockdoc** » Sat Apr 28, 2012 8:18 pm

timelessbeing wrote:Short the sensor wire to ground, and turn on ignition. Gauge should register max temp. If not, wiring is faulty.

The sensor for the gauge and the sensor for the ECM are two different things. That method wouldn't work. The temp gauge sensor is in the head and the other is by the thermostat housing.

For the new connector, splice, solder and heat shrink the connections and you'll be fine.

Chevy & GMC Vans

Chevy & GMC Vans

Very persistant code 15

Very persistant code 15

Re: Very persistant code 15

Re: Very persistant code 15

Re: Very persistant code 15

Re: Very persistant code 15

Re: Very persistant code 15

Re: Very persistant code 15

Re: Very persistant code 15

Re: Very persistant code 15