Voltage drop when ac compressor runs - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Cherokee & Comanche Forums > XJ Cherokee Technical Forum > Voltage drop when ac compressor runs

RIGID LED Light Blowout Sale - All Sizes, All Series, all Stainless Steel Door Hinge PinsPoly Door Hinge Bushings

Reply
Unread 05-20-2006, 12:07 PM   #1
kyleboy7
Registered User
 
Join Date: Mar 2004
Location: Rochester MI
Posts: 38
Voltage drop when ac compressor runs

When I put on my A/C my voltage drops a whole bunch. Is this the alternator going out or something else perhaps?

__________________
Gots me a 93 cherokee
kyleboy7 is offline   Reply With Quote
Unread 05-20-2006, 12:51 PM   #2
Jeppy
Member
 
Jeppy's Avatar
 
Join Date: Nov 2005
Location: Florida Panhandle
Posts: 263
if your battery is good it may be a loose (high resistance) ground or positive 12V connection. check them all, if not, look at alt next
__________________
2014 White Jeep Cherokee Trailhawk
3.2L
Leather Interior Group, Canyon Brown
Black Hood Decal
MFG build date 10/13
Black Keys all the way up on the stereo:
"Well my Next-Jeep, be nothin' like my Ex-Jeep"
Jeppy is offline   Reply With Quote
Unread 05-26-2006, 02:40 AM   #3
kyleboy7
Registered User
 
Join Date: Mar 2004
Location: Rochester MI
Posts: 38
Ok so i did a bit of investigating... Ive discovered that sometimes when i start the engine the belt will squeak... (i think its the belt) and the voltage drops the belt stops sweaking and the voltage goes back up the squeaking is also there when i turn the ac on it will go away if i give it a bit of a rev. The battery is good its about 1yr old optima red top, belt tension appears fine. another note tho is when i turn just the fan on the voltage drops slightly.

Is this a pointing at the alternater or something else?
__________________
Gots me a 93 cherokee
kyleboy7 is offline   Reply With Quote
Unread 05-26-2006, 09:59 AM   #4
dakotus
Registered User
 
Join Date: Apr 2004
Location: Cleveland, Ohio
Posts: 696
I thought this was normal? The AC Compressor uses quite a bit of currrent I thought, enough to make the voltage gage drop for a second. no?
__________________
1999 Cherokee Sport
dakotus is offline   Reply With Quote
Unread 05-26-2006, 10:50 AM   #5
mylt1
Registered User
 
Join Date: Oct 2005
Location: Virginia
Posts: 5,881
if your belt is squeeling you may want to tighten the belt. i had a simular problem a while back.
mylt1 is offline   Reply With Quote
Unread 05-26-2006, 11:16 AM   #6
MGrobe
Man In Black
 
MGrobe's Avatar
1998 XJ Cherokee 
 
Join Date: Oct 2003
Location: Chicago-area (Western Suburbs)
Posts: 2,295
Might be totally normal. What used to happen with my 98 XJ is that when the clutch on the AC compressor engages, so does the electric fan. And the electric fan would draw enough current to cause my headlights to noticeably dim. The AC compressor clutch would stay engaged for roughly 10 seconds and the fan would keep running during this period.
__________________
-Marc-
Sweet Pea 1998 - XJ
http://www.grobe.us/Jeep
- JeepForum Rules - Become a Premium Member or Vendor
For Sale: (4) AR 767-5766 Wheels (used) 15x7, 5x4.5, 4.5BS - for local pickup in the Chicago-area
MGrobe is offline   Reply With Quote
Unread 05-26-2006, 11:49 AM   #7
Islandroaddie96
Registered User
1996 XJ Cherokee 
 
Join Date: Jul 2003
Location: Anacortes
Posts: 1,538
Your belt is too loose.
__________________
1996 XJ Sport
4.0L I6 HO; AW4; NP242; D30/D35; 3" Homebrew BB; 31" x 10.5" BFG A/T
Six Harbor Freight Lights (el cheapo)

GREEN JEEP CLUB MEMBER #74
Islandroaddie96 is offline   Reply With Quote
Reply
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.