The Chrysler Minivan Fan Club Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
31 Posts
Discussion Starter #1
2003 Caravan SE w/3.3 litre & 165,000 km. On going issues with my check engine light. Runs well, unfortunately horrible mileage and persistent check engine light. I removed wipers/cowling and with engine warmed up ran all around the intake manifold, vac hoses etc with my propane sniffer without finding any leaks. Running sensor diagnostics with a friends Elm 327, the only thing unusual I could find were the oxygen sensor readings. Lower is fine, fluctuating below 1 volt, Upper is reading a constant zero. Removing the upper sensor was pretty simple with the wiper cowl removed, might even replace the PVC valve while I have it off, anyways .... before I order a new upper sensor ($139), I'd like to do a bench test on the old one. Unfortunately, Haynes is pretty weak when it comes to narratives, illustrations and schematics .... so I,m looking for pin out diagram.

This is a 4 wire sensor, 2 for the heater and 2 for the sensor output. There are 2 black wires, 1 white and 1 purple or blue (to a color blind person). I know one of the black wires is a 12 volt input for the heater .... just not sure which two pins are for the sensor output? .... :blink:
 

·
Premium Member
Joined
·
10,109 Posts
I think the 2 black wires are for the heater.
 

·
Vendor
Joined
·
565 Posts
Here is what I found in my 2007 FSM for the 3.3/3.8 upstream O2 sensor from the wiring diagram. The plug pinout has pins 1 & 2 swapped, however, 3 & 4 are the same.

Pin Color Function
== === =======
1 BK/LG Heater Control
2 BR/LG Heater Ground
3 BR/DG O2 Return
4 DB/LB O2 Signal

Frank
96 Grand Voyager retired
99 DGC Sport retired at 137K miles (still running fine for my friend)
07 T&C SWB with 30650 miles
 

·
Registered
Joined
·
31 Posts
Discussion Starter #4 (Edited)
Thanks for the help ... I'm pretty sure now the 2 blacks are for the heater, blue is the signal and white is for the signal ground. Will try to confirm in the morning. Closest thing I could find on the net was sort of generic table which is probably pretty close. Chrysler must be the Type B. I get about 3.5 ohms resistance between the two blacks.

Type A Type B Type C HONDA GM TITANIA
Heater White = Black = Purple = Black = Brown = White
Heater White = Black = White = Black = Brown = Red
Signal Black = Blue = Black = White = Purple = Black
Ground Gray = White = Gray = Green = Tan
 

·
Registered
Joined
·
31 Posts
Discussion Starter #7
I was getting a persistent P0171 (lean) code. Broke down and picked up a replacement O2 sensor from a local dealer this morning. Reset my codes and my problem seems to be gone. Monitoring sensors, I am getting a sensor response now from the upstream sensor, fluctuating happily with the downstream sensor ..... so all appears well. Thanks for all the help ... Great forum
 
1 - 7 of 7 Posts
Top