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Monday, October 31, 2016

Where is the Relay?


Relay or No Relay?

Not all vehicles stay as built by the factory. SureTrack community member thewrench had a diesel Dodge Pickup in their shop where the fuel system didn’t match the factory information because it had been retrofitted. They posed the question to the community, and with the help of fellow community member DieseltechJon and others, they were able to resolve the issue.

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2004 Dodge Pickup R3500 5.9L Diesel
No Power to the Fuel Pump, Replaced Relay
Truck will not start and repair information states that truck is equipped with a fuel lift pump attached to the fuel filter/water separator housing but this truck does not. Found references to retrofits on some of these trucks where an in-tank lift pump is used which apparently this truck has.

Diagnostic Steps Performed/Parts Replaced
We have no power to the fuel pump wire at the tank, and have not been able to find a fuel pump relay although retrofit repair information shows that there is a fuel pump relay, but does not specify location. C1 Pin 19 at the ECM shows to be Fuel Pump Relay Control and C1 Pin 6 shows to be Fuel Pump Relay Return. Underhood power control center does not show any of the relays to be a ‘Fuel Pump Relay’.
Best Answer from Community
If this truck had the retrofitting done check the driver side firewall area for the relay. Usually somewhere between the battery and firewall.
Faulty retrofit fuel pump relay.

Replaced fuel pump relay and truck now starts.

This is a Real Fix from Mitchell 1′s new SureTrack®
expert information source. These documented issues from actual shop repair orders demonstrate how SureTrack can help you correct issues that are not easily diagnosed using OEM information alone. SureTrack is currently available free in our ProDemand product.


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