03 liberty

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Johnlovett

New Member
Joined
May 13, 2016
Messages
3
Reaction score
2
Location
Tennessee
Thursday night while driving down the interstate with the cruise control set my check engine light came on then the battery light came on then it very gently slipped out of gear. I cut off the CC then tried to give it gas but nothing. After a few seconds it gently slipped into gear & I was back to running 75mph. It jumped out of gear 3 more times before I covered the 100 miles left on my trip. The codes that were generated were P1682 & P1491. Has anyone dealt with this? Thanks in advance. John
 

LibertyTC

Well-Known Member
Staff member
Moderator
Joined
Oct 24, 2008
Messages
9,081
Reaction score
1,747
Location
B.C. Canada
Welcome, the Jeep will do strange things if the charging system or battery has any issues.
P1682 =Charging System Voltage Too Low.
Ensure both battery terminals are clean, free of any corrosion, & tight.
How old is this battery? -get it load tested. Use a Volt ohm meter with Jeep running & report back what the output voltage reading is.
P1491= Cooling Fan Relay Control Circuit according to our Generic Chrysler Diagnostic Trouble Code list
https://www.jeepkj.com/threads/generic-chrysler-diagnostic-trouble-code-list.39860/
 

Johnlovett

New Member
Joined
May 13, 2016
Messages
3
Reaction score
2
Location
Tennessee
Welcome, the Jeep will do strange things if the charging system or battery has any issues.
P1682 =Charging System Voltage Too Low.
Ensure both battery terminals are clean, free of any corrosion, & tight.
How old is this battery? -get it load tested. Use a Volt ohm meter with Jeep running & report back what the output voltage reading is.
P1491= Cooling Fan Relay Control Circuit according to our Generic Chrysler Diagnostic Trouble Code list
https://www.jeepkj.com/threads/generic-chrysler-diagnostic-trouble-code-list.39860/
Thanks a lot. I had to replace the pcm(I think) about a year ago. Since then the fan motor has been clicking while the jeep is off running my battery down. I dont drive it much. It's a older battery. Everything you said makes complete sense. The fan motor clicks about every 2 seconds & the fan blade jumps slightly when it does but never spins all the way around or engages while the engine is off. But the engine runs fine & cools properly while running even in the middle of summer. This is the first issue since changing the pcm that made the check engine light come on other than at start up. Again thanks for the info. I think I have a starting point.
 

LibertyTC

Well-Known Member
Staff member
Moderator
Joined
Oct 24, 2008
Messages
9,081
Reaction score
1,747
Location
B.C. Canada
To further assist you re the relay, here is the 03 Factory Manual: http://www.colorado4wheel.com/manuals/Jeep/KJ/2003JeepKJServiceManual.pdf
I cant remember @ the moment if 03 had the external relay. My 04 has high/low under the hood junction block ones.

Lead acid batteries only tend to last 3-4 years. For the Jeep try to find one with 800+ cold cranking amps.
If replacement is needed, for a few $ more Napa or Exide AGM (absorb glass matt) last longer & are a deep cycle battery, that can last 6 years.
Odyssey batteries are virgin lead and the best but $$ (AGM) 34/78DT.
My Odyssey is around 9 years old and still has 70% or 750CCA left on the load test!
AGM's are also better sealed, so you wont get terminal corrosion.
What is the voltage reading when Jeep is running?
 

Billwill

Full Access Member
Joined
Nov 26, 2009
Messages
2,193
Reaction score
668
Location
White River, South Africa
Download the 2003 Jeep KJ Service Manuals as per LibertyTC's link.

The Fan Relay on the 2003 3.7 gasser is an externally mounted Solid State Relay.

This relay is a variable relay ie. unlike a normal mechanical relay as you will find in the Fuse Box under the hood or on the interior fuse...this Solid State Relay is "pulsed" ON/OFF by the PCM to slow down or speed up the fan. This Relay is bolted near the Fan in the engine bay....will have four wires going to it....Dark Blue/Pink, Yellow, Light Green and Black with Orange Stripe. This Black/Orange Stripe wire goes direct to ground so I would splice a wire onto this wire and ground it to Engine/Chassis somewhere nearby.;)

The 2003 KJ I believe is the only KJ to use this type of relay and they are known to cause problems which is probably why it got dropped in later KJ models!:confused:

So you could try find a new one or one at a Breaker Yard from a 2003 KJ!

The Component Location in the Wiring Diagram Section 8W is supposed to direct you to the relevant Circuit Diagrams for this Radiator Fan Relay but Jeep decided to rather make this into a Treasure Hunt!o_O

So the relevant pages you need are 8W-30-23, 8W-15-5, 8W-80-85/86/7.

If you cannot simply replace the relay...it will be pretty hard to track down a problem in the wiring!:(

So in this case I would suggest that you fit a small ON/OFF switch inside the cabin that interrupts Fuse #2 40 Amp inside the PDC under the Hood ie. cut off the Dark Blue/Pink wire as shown on 8W-30-23 and fit your switch into the cut-off section.
This way you can stop the fan from clicking ON/OFF when you turn off the ignition but do not forget to switch it back on when you drive off....assuming the Fan does actually switch ON/OFF while you are driving.o_O

If the Radiator Fan Relay is Faulty I think that the fan will either not run at all or will run as soon as engine is running!;)
 
Last edited:

LibertyTC

Well-Known Member
Staff member
Moderator
Joined
Oct 24, 2008
Messages
9,081
Reaction score
1,747
Location
B.C. Canada

Johnlovett

New Member
Joined
May 13, 2016
Messages
3
Reaction score
2
Location
Tennessee
Welcome, the Jeep will do strange things if the charging system or battery has any issues.
P1682 =Charging System Voltage Too Low.
Ensure both battery terminals are clean, free of any corrosion, & tight.
How old is this battery? -get it load tested. Use a Volt ohm meter with Jeep running & report back what the output voltage reading is.
P1491= Cooling Fan Relay Control Circuit according to our Generic Chrysler Diagnostic Trouble Code list
https://www.jeepkj.com/threads/generic-chrysler-diagnostic-trouble-code-list.39860/
I checked it Saturday with a tester & it was reading normal alternator output.
 

LibertyTC

Well-Known Member
Staff member
Moderator
Joined
Oct 24, 2008
Messages
9,081
Reaction score
1,747
Location
B.C. Canada
Normal? What was the actual voltage reading 13.9 volts ?
Next would also be to test it under load: running, headlights on, blower fan on high, radio on interior lights on, re-defoogger on. What is that voltage reading then?
Battery should be load tested as well. You want to ensure you have a good battery.
Charge the battery fully, before the load test.
 

sleazy rider

Retired moto tech and gearhead
Joined
Dec 8, 2020
Messages
540
Reaction score
499
Location
SE Michigan
Normal? What was the actual voltage reading 13.9 volts ?
Next would also be to test it under load: running, headlights on, blower fan on high, radio on interior lights on, re-defoogger on. What is that voltage reading then?
Battery should be load tested as well. You want to ensure you have a good battery.
Charge the battery fully, before the load test.

Or swing by your local Autozone/NAPA/O’Reilly’s to let them test the battery and charging system free of charge.
 

Latest posts

Members online

Top