99 Intake Air Temp Sensor Circuit Question
Thread Starter
Burning Brakes
Joined: Oct 2013
Posts: 1,030
Likes: 72
From: Seminole, FL
99 Intake Air Temp Sensor Circuit Question
My 99 Coupe getting Check Engine light.
Code is P0113 IAT Circuit HIGH.
Open circuit on TAN lead between Sensor and PCM.
I've actually pulled the PCM and checked condition of connectors.
Proved continuity on Purple, Ckt # 719, Lead # 57 on PCM Connector #2, the RED one.
Proved open circuit on Tan, Ckt # 472, Lead # 25 on PCM Connector #2, the RED one.
My question here would be, is there a 'common Breakage Point', like a spot somewhere in the harness that people have seen this wire break on a number of cars?
Thought I'd ask, before I start chasing through the entire harness between the PCM and sensor.
Code is P0113 IAT Circuit HIGH.
Open circuit on TAN lead between Sensor and PCM.
I've actually pulled the PCM and checked condition of connectors.
Proved continuity on Purple, Ckt # 719, Lead # 57 on PCM Connector #2, the RED one.
Proved open circuit on Tan, Ckt # 472, Lead # 25 on PCM Connector #2, the RED one.
My question here would be, is there a 'common Breakage Point', like a spot somewhere in the harness that people have seen this wire break on a number of cars?
Thought I'd ask, before I start chasing through the entire harness between the PCM and sensor.
Melting Slicks
Joined: Jul 2015
Posts: 2,290
Likes: 231
From: Round Rock Texas
Was checking my sons 96 camaro when I noticed on the computer the air temp sensor was reading when started 109f. Hum ohmed out senor and it was reading in k ohms. Replaced part on amazon was $12. Now when I start it reads ambient temp.
Thread Starter
Burning Brakes
Joined: Oct 2013
Posts: 1,030
Likes: 72
From: Seminole, FL
Wish it was that simple here.
Installed New Dealer Chevy part (sensor) within an hour of problem surfacing.
No Change.
Had my OTC EVO plugged into the car, watching the sensor readings, and no change whatsoever.
Which led to in-depth diagnosis, using my factory service manuals.
UGH..
Installed New Dealer Chevy part (sensor) within an hour of problem surfacing.
No Change.
Had my OTC EVO plugged into the car, watching the sensor readings, and no change whatsoever.
Which led to in-depth diagnosis, using my factory service manuals.
UGH..
Team Owner
Joined: Jul 2012
Posts: 34,479
Likes: 532
From: Central PA. - - My AR15 identifies as a muzzleloader
I believe in the Beer Fairy
My 99 Coupe getting Check Engine light.
Code is P0113 IAT Circuit HIGH.
Open circuit on TAN lead between Sensor and PCM.
I've actually pulled the PCM and checked condition of connectors.
Proved continuity on Purple, Ckt # 719, Lead # 57 on PCM Connector #2, the RED one.
Proved open circuit on Tan, Ckt # 472, Lead # 25 on PCM Connector #2, the RED one.
My question here would be, is there a 'common Breakage Point', like a spot somewhere in the harness that people have seen this wire break on a number of cars?
Thought I'd ask, before I start chasing through the entire harness between the PCM and sensor.
Code is P0113 IAT Circuit HIGH.
Open circuit on TAN lead between Sensor and PCM.
I've actually pulled the PCM and checked condition of connectors.
Proved continuity on Purple, Ckt # 719, Lead # 57 on PCM Connector #2, the RED one.
Proved open circuit on Tan, Ckt # 472, Lead # 25 on PCM Connector #2, the RED one.
My question here would be, is there a 'common Breakage Point', like a spot somewhere in the harness that people have seen this wire break on a number of cars?
Thought I'd ask, before I start chasing through the entire harness between the PCM and sensor.
I don't have any good ideas for what it could be given what you've said. If all shows 'good', I'd be inclined to think I was checking the wrong wires or something of that nature. Perhaps take a good look at the actual connector that attaches to the sensor itself and see if the contacts in that are clean and make good connections.
Maybe put an ohm meter on the sensor itself and see if it changes value as the sensor is warmed and cooled. Bought a bum sensor possibly?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Art
The MOST COMMON C5 rub thru spot for engine sensor functions is at the rear of the drivers side fuel rail where the drivers side engine harness bends around the black metal bracket at the rear of the drivers side fuel rail (The bracket is actually a safety device to keep the fuel rail from sheering off in an accident)
Look for a rub mark in the black harness tape or untape it and look for damaged wires:
The MOST COMMON C5 rub thru spot for engine sensor functions is at the rear of the drivers side fuel rail where the drivers side engine harness bends around the black metal bracket at the rear of the drivers side fuel rail (The bracket is actually a safety device to keep the fuel rail from sheering off in an accident)
Look for a rub mark in the black harness tape or untape it and look for damaged wires:
