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Really bad fuel pump circuit problem

  • Thread starter Thread starter Ruffellbaker
  • Start date Start date May 18, 2011

Ruffellbaker

New Member
Mar 29, 2011
23
0
1
Hagerstown/Cumberland MD
May 18, 2011
#1
  • May 18, 2011
  • #1
So my fuel pump went out last week and I havent been able to start my car since i put the new one in. It keeps blowing the fuel pump fuse and the battery goes dead overnight without a fuse being in place at all. So I imagine that theres a short before the fuse? I just replaced my CCRM a month ago and went ahead and got another new one just to be sure. Ive tested everywhere I can think of and cant find the problem. Also today I was out trying to find the problem and now the radio has no power and there is no blown fuse and theres a beeping noise coming from the dash when I turn the key on. Ive also checked voltage where the fuse goes, Im getting battery voltage on the side facing the front of the car and like 20mv facing the firewall. Why am I getting voltage on both sides.
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
May 18, 2011
#2
  • May 18, 2011
  • #2
Ruffellbaker said:
Ive also checked voltage where the fuse goes, Im getting battery voltage on the side facing the front of the car and like 20mv facing the firewall. Why am I getting voltage on both sides.
Click to expand...
back feeding through the attached devices. 20 mV is so low as to be close the the limit of the VOM.

Just as a guess, there is a pinched wire. Separate the round connector in the center gas tank. On the part towards the gas tank, measure the resistance between the RD/BK and ground as well as BN/PK and ground. Post. The Ohm value should be high. If not, it indicates there is a short inside the tank.

Next inject 12 volts to the RD/BK and BN/PK wire. This will force the fuel pump to run. Post how many amps the pump is drawing.
 

Ruffellbaker

New Member
Mar 29, 2011
23
0
1
Hagerstown/Cumberland MD
May 18, 2011
#3
  • May 18, 2011
  • #3
what should the resistance of the pump be? Im pretty sure the last time I checked it I got around 2 ohms
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
May 18, 2011
#4
  • May 18, 2011
  • #4
Didn't ask for the resistance of the pump itself. Asked for the resistance to GROUND.

The amp draw of the pump will tell about the health of the pump. Really shouldn't matter as the pump is new anyway.
 

Ruffellbaker

New Member
Mar 29, 2011
23
0
1
Hagerstown/Cumberland MD
May 18, 2011
#5
  • May 18, 2011
  • #5
Well whenever I tested that connector I got around 2 ohms from the brwn and pink wire to the black
 
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