Code dilemma on '98 XJ
#1
Newbie
Thread Starter
Join Date: Mar 2012
Location: Colorado Springs, CO
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1998
Model: Cherokee
Engine: 4.0L Six
Code dilemma on '98 XJ
Son is home from college for Thanksgiving break with his (my) 1998 Jeep XJ. Getting ready to do a lift on it, and notice the CEL ablaze. Already changed the battery (Oct 2012) and Crankshaft Position Sensor (Sep 2013), so a little lost and in need of help. Pulled the codes and found the following:
P1682 - charging system voltage too low (alternator? PCM?)
P0320 - no crank reference signal at PCM (CPS? PCM?)
P0420 - catalyst system efficiency below threshold (o2 sensor? catalytic convertor)
P0138 - o2 sensor failure
Did a comprehensive forum search, but no luck. Old girl starts and runs fine (even in the cold - 10 deg in Colorado this morn.), but volt gauge is reading 14 at start, then moves to just above 9. No dying issues. I've used the search function, and smacked my head into enough books to last lifetime. May not even be connected issues, but wanted to check first. Thanks in advance!
Cheers,
Pappy
P1682 - charging system voltage too low (alternator? PCM?)
P0320 - no crank reference signal at PCM (CPS? PCM?)
P0420 - catalyst system efficiency below threshold (o2 sensor? catalytic convertor)
P0138 - o2 sensor failure
Did a comprehensive forum search, but no luck. Old girl starts and runs fine (even in the cold - 10 deg in Colorado this morn.), but volt gauge is reading 14 at start, then moves to just above 9. No dying issues. I've used the search function, and smacked my head into enough books to last lifetime. May not even be connected issues, but wanted to check first. Thanks in advance!
Cheers,
Pappy
#2
Junior Member
Join Date: Nov 2013
Location: Windsor, Ontario / Detroit, Michigan
Posts: 42
Likes: 0
Received 1 Like
on
1 Post
Year: 2014
Model: Grand Cherokee
Engine: 3.6
Why not pull the alternator and run it over to Autozone for a quick (free) check? At least it will rule out the most obvious cause.
#3
Newbie
Thread Starter
Join Date: Mar 2012
Location: Colorado Springs, CO
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1998
Model: Cherokee
Engine: 4.0L Six
Good call Roy, and I'm in the process of taking that advice as we speak. I'm new to the Jeep world with little PCM experience, and since the PCM is a probable in both of the first codes and the alternator is only a probable in the first, I wanted to see if people usually found 1682 and 0320 when PCMs were on their way out. Thanks again.
#4
Junior Member
Join Date: Nov 2013
Location: Windsor, Ontario / Detroit, Michigan
Posts: 42
Likes: 0
Received 1 Like
on
1 Post
Year: 2014
Model: Grand Cherokee
Engine: 3.6
Could be the PCM, but you can get all sorts of strange and seemingly unrelated codes when the charging system is not functioning properly. Plus, I am a firm believer in trying the easy (and inexpensive) fixes first.
#5
CF Veteran
Join Date: Jul 2012
Location: SD
Posts: 1,395
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1998
Model: Cherokee
Engine: 4.0
Thread
Thread Starter
Forum
Replies
Last Post
4WD4EVER
Modified XJ Cherokee Tech
28
07-28-2023 07:12 PM
sluger17
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
9
07-08-2023 07:08 AM
dennismo
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
1
04-15-2018 05:57 PM
tleed
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
3
10-04-2015 01:20 PM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)