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Discussion Starter #1
I have no spark and no signal power to the switch side of the pump relay, all fuses and relays are good and I’ve tested the kill switch, ecu, coil and pump they test fine. The DFI is deleted and it has a tether and it’s fine. No fuel controller stock ecu and coil. Any ideas ? I checked the codes and got 31 and 41. Battery is also fine
 

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I have no spark and no signal power to the switch side of the pump relay, all fuses and relays are good and I’ve tested the kill switch, ecu, coil and pump they test fine. The DFI is deleted and it has a tether and it’s fine. No fuel controller stock ecu and coil. Any ideas ? I checked the codes and got 31 and 41. Battery is also fine
Welcome to the Forum...!!

Code 31 is the vehicle down sensor...Check the vehicle down sensor output voltage...how to & location see picture below
 

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Discussion Starter #3 (Edited)
The down sensor was deleted by the original owner, would that cause it to throw that code ? How do I check if it was done correctly
 

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Yes it has that exact one is there a way to test if it’s bad? Or a way to bypass it to make sure it’s the problem
First you need to test the power from the ECU to the sensor bypass...
Vehicle-down Sensor Power Source Voltage
Connections to Sensor Connector
Meter (+) → LB lead
Meter (–) → BR/BK lead
should be within 4.75~5.25v DC ...

If yes, Then test the output of the sensor bypass, It has to remain hooked up, key ON & you will have to access the wires to test it...
Vehicle-down Sensor Output Voltage
Connections to Sensor Connector
Meter (+) → Y/G lead
Meter (–) → BR/BK lead

The voltage is to be within this range to be good...!!!
Output Voltage at Sensor
3.7 ∼ 4.4 V DC
 

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Discussion Starter #7
Good power from LB to br/bk.
6v from y/g and br/bk
So this Means the the bypass is bad correct?
 

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Good power from LB to br/bk.
6v from y/g and br/bk
So this Means the dele
How many millivolts is "Good power"...??

What is the exact input voltage on the LB ?.. Is it above, below or within range of 4.75~5.25v ..???

If 6v is the measure of the output voltage, other sensor might be damaged too due to a bad ECU

Do this test again...!!!
Vehicle-down Sensor Power Source Voltage
Connections to Sensor Connector
Meter (+) → LB lead
Meter (–) → BR/BK lead
should be within 4.75~5.25v DC ...
 

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And still 6v on the y/g and bk and br so 6v is more then 5v that means check the ecu ground
Vehicle-down Sensor Output Voltage
Connections to Sensor Connector
Meter (+) → Y/G lead
Meter (–) → BR/BK lead

The voltage is to be within this range to be good...!!!
Output Voltage at Sensor range 3.7 ∼ 4.4 V DC

Your output voltage is 6v thus
The tip over eliminator/delete is bad & needs to be replaced with another KMS eliminator or a vehicle down sensor...!!

or
 

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Discussion Starter #16
Thank you man I was completely stumped and skipped over this in the Manuel because of the delete
 

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Sorry to say that didn’t fix it, does this leave it to a wiring short or bad ecu
if the down sensor or KMS bypass is reading in range 3.7~4.4 dcv then it could be the ECU...

Also the output voltage can not read more than the input voltage...example input of 4.75 DCV output reading 5v or higher

Vehicle-down Sensor Output Voltage
Connections to Sensor Connector
Meter (+) → Y/G lead
Meter (–) → BR/BK lead

The voltage is to be within this range to be good...!!!
Output Voltage at Sensor range 3.7 ∼ 4.4 V DC
 

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Discussion Starter #19
I have 5.01v on the LB wire and 6.02 on the Y/G.
Does this mean bad ecu and it burned up my kms bypass again ?
 
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