TIPM Fuel Pump Relay Bypass Diagram: A Complete Guide to Fixing Your Crank No Start Issue

If your Chrysler, Dodge, Jeep, or Ram vehicle cranks but won't start, especially when cold, the most likely culprit is a failed fuel pump relay inside the Totally Integrated Power Module (TIPM). The good news is that you don't need to spend $1,500+ on a new TIPM from the dealer. A TIPM fuel pump relay bypass is a proven, inexpensive, and permanent solution that restores fuel pump operation by routing power through an external relay or bypass cable. This guide provides step-by-step diagrams and instructions for three different bypass methods, with the external relay method being the most reliable long-term fix recommended by mechanics and factory service bulletins.

Understanding the TIPM Fuel Pump Relay Problem

The TIPM is a central electrical control unit located under the hood of your vehicle. It acts as a modern fuse box and manages power distribution for many systems, including the fuel pump relay. The fuel pump relay is soldered directly onto a circuit board inside the TIPM, making it non-serviceable without specialized tools and soldering skills.

Over time, the internal relay fails due to faulty diodes, worn contacts, or cracked solder joints. Electrical stress, temperature changes, and vibration cause these failures. The result is an intermittent or complete loss of power to the fuel pump, leaving you stranded with a crank-no-start condition.

Common Symptoms of a Bad Fuel Pump Relay

  • Multiple attempts to start, especially in the morning when the vehicle is cold
  • Vehicle acts like it's out of gas (cranks but won't start)
  • Engine starts briefly then dies seconds or minutes later
  • Starts fine with starter fluid but won't stay running
  • Unexplained battery drainage because the relay is stuck in the "on" position
  • Fuel pump operates intermittently or not at all
  • No fuel pump noise when turning the key to the "on" position (you should hear a 2-second hum from the rear of the vehicle)

A quick diagnostic test: While cranking the engine, have someone measure voltage on the M25 fuel pump fuse in the under-hood fuse box (TIPM). If the fuse does not have a constant 12V while cranking, the fuel pump relay has failed.

Three Ways to Bypass the TIPM Fuel Pump Relay

There are three main approaches to fixing this issue. The table below compares them, and the following sections provide detailed diagrams and instructions for each method.

Method Cost Difficulty Time Permanence
Bypass Cable (Temporary) $25-$35 Easy 5 minutes Temporary only
External Relay (Permanent) $15-$30 Moderate 1-2 hours Permanent
Plug-in Bypass Module $59-$129 Easy 5-10 minutes Semi-permanent

Method 1: Temporary Bypass Cable Using Fuse Taps

This is the quickest way to get your vehicle running again, but it should only be used as a temporary fix. The bypass cable takes power from an alternate fuse slot (M37 or F90/F91) and feeds it directly to the fuel pump fuse slot (M25 or F70), bypassing the faulty relay.

What You Need

  • Two 20 amp ATM fuse taps (micro2 or mini-blade depending on your TIPM style)
  • One 20 amp fuse (for the M37 side)
  • Wire connectors or butt connectors
  • Heat shrink tubing or electrical tape

Step-by-Step Diagram Instructions

Step 1: Identify the correct fuse slots on your TIPM

  • M25 or F70: This is the fuel pump fuse slot. Remove the 30A fuel pump fuse from this slot.
  • M37 or F91: This is the run/start fuse slot. This slot only provides power when the engine is running or being started. Remove the existing fuse from this slot.
  • F90: This is the accessory power slot (cigarette lighter). For testing purposes only, you can use F90, but it will leave the fuel pump running when the engine is off.

Step 2: Assemble the bypass cable

Take two 20 amp fuse taps. Remove the butt connector from one of them, strip the wire, and crimp or solder it to the wire from the other fuse tap. Use heat shrink tubing to insulate the connection. The assembly should have two fuse tap ends, one for each slot.

Step 3: Install the fuses

  • On the end that goes into the M37 slot, install a 20 amp fuse in the top position of the fuse tap.
  • Leave the bottom fuse position on the M25 end empty. This is critical to avoid backfeeding voltage to the run/start circuit.

Step 4: Plug the cable in

  • Insert the M37 end of the cable into the M37 slot with the wire side pointing toward the center of the TIPM.
  • Insert the M25 end of the cable into the M25 slot with the wire side also pointing toward the center of the TIPM.
  • Make sure the connections are snug and secure.

Step 5: Start the vehicle

Turn the key to the run position, then start the engine. If the fuel pump is working, you should hear it prime and the engine should start.

Important Warnings for Temporary Bypass Cable

  • Do not use this as a permanent fix. The fuse tap connections can become loose over time, and bad connections have been known to cause fires.
  • The M7 slot (F90) leaves the fuel pump running when the engine is off. Only use the M37 slot for bypass mode, as it only powers the fuel pump when the engine is running or being started.
  • Remote start may not work with this cable installed.
  • Monitor the cable for heat. If the wire feels hot to the touch, the cable or connections may be overloaded.

Method 2: Permanent External Relay Bypass (Recommended)

This is the factory-approved method that provides a permanent, safe, and reliable solution. It involves installing an external relay that takes over the fuel pump switching function, completely bypassing the failed internal relay. This is the method described in the factory service bulletin for Chrysler, Dodge, and Jeep vehicles.

What You Need

  • 30A 12V DC normally open relay (standard automotive relay)
  • 20A inline fuse holder with 20A fuse
  • 16-22 AWG automotive-grade wire (about 3-4 feet)
  • 1/4 inch eyelet terminal for battery connection
  • Heat shrink tubing
  • Butt connectors
  • Corrugated wire loom
  • Electrical tape
  • Zip ties
  • Multimeter (for testing)

TIPM Connector Identification

Before starting, locate the TIPM connectors. The diagram below shows the three connectors you need to access. The TIPM has multiple connectors labeled C1 through C7. You will be working with connectors C1 and C5.

Connector C1 (usually the largest connector, located on the driver's side of the TIPM):

  • Terminal 40: Brown wire

Connector C5 (located on the passenger side of the TIPM):

  • Terminal 10: Dark blue/orange wire
  • Terminal 38: Pink/light green wire

Step-by-Step External Relay Wiring Diagram

Step 1: Locate the wires and prepare the connections

Unplug connectors C1 and C5 from the TIPM. Identify the wires by their colors. Use a multimeter to verify the correct wires before cutting anything.

Step 2: Cut and insulate the brown wire

Locate the brown wire on terminal 40 of connector C1. Cut it approximately 1 inch away from the connector. Insulate the wire end that goes into the connector with heat shrink tubing. This disconnects the faulty internal relay from the circuit. The other end of the wire (going toward the vehicle harness) will be connected to the new relay.

Step 3: Cut and insulate the dark blue/orange wire

Locate the dark blue/orange wire on terminal 10 of connector C5. Cut it 1 inch away from the connector. Insulate the wire end going into the connector. The other end will be connected to the new relay.

Step 4: Do not cut the pink/light green wire

Locate the pink/light green wire on terminal 38 of connector C5. Do not cut this wire. Instead, solder a new wire to it, or use a tap connector. This wire provides the run/start signal to the new relay.

Relay Terminal Connections

Now wire the external relay using the diagram below:

Relay Terminal 85 (Coil Ground):
Connect to the cut end of the brown wire from terminal 40 of connector C1. This wire provides the ground path for the relay coil.

Relay Terminal 86 (Coil Power):
Connect to the pink/light green wire on terminal 38 of connector C5 (the wire you did not cut). This wire provides 12V power to the relay coil when the ignition is in the run or start position.

Relay Terminal 87 (Normally Open Output):
Connect to the cut end of the dark blue/orange wire from terminal 10 of connector C5. This wire carries power to the fuel pump.

Relay Terminal 30 (Common Power Input):
Connect to battery positive. Use the 1/4 inch eyelet terminal to connect to the battery positive terminal or the TIPM B+ post. Install the 20A inline fuse holder on this wire as close to the battery as possible. This provides constant 12V power to the relay.

Completing the Installation

Step 5: Secure all connections

Solder all connections for maximum reliability, then cover each with heat shrink tubing. If you cannot solder, use high-quality crimp connectors and apply dialectic grease to prevent corrosion.

Step 6: Protect the wiring

Wrap the wires in corrugated wire loom to protect them from heat, moisture, and abrasion. Use zip ties to secure the wiring away from moving parts and hot surfaces.

Step 7: Mount the relay

Screw the relay onto a clean metal surface near the TIPM. Make sure the relay is mounted securely and the wiring is not strained.

Step 8: Test the system

Reconnect the TIPM connectors C1 and C5. Turn the ignition to the run position. You should hear the fuel pump prime for 2 seconds. Start the engine. If it starts and runs smoothly, the bypass is working correctly.

Method 3: Plug-in Bypass Module (Easy Alternative)

Several companies offer plug-in bypass modules that eliminate the need for cutting wires or soldering. These modules are installed in minutes by simply plugging them into the TIPM connectors. The most popular options include:

  • Vertical Visions TIPM Bypass Board: A full-featured module that plugs into the TIPM and provides diagnostic LEDs for monitoring relay status, fuel pump operation, and run/start signals. It costs approximately $129 and includes a 2-year warranty.
  • Vertical Visions Simple Bypass Cable: A no-frills cable that plugs into the M37 and M25 fuse slots. It costs approximately $25 and is intended for temporary use, though many customers use it long-term.

These plug-in modules are ideal for customers who are not comfortable with soldering or cutting wires. They are also a good option for testing purposes to confirm that the fuel pump relay is the actual problem before investing time in a permanent fix.

Diagnostic Tips Before Installing Any Bypass

Before you start cutting wires or installing bypass cables, it is essential to confirm that the fuel pump relay is the problem and not the fuel pump itself. Here are two simple tests you can perform:

Test 1: Fuel Pump Relay Test (Using a Bypass Cable with LED)

If you purchase a standard TIPM bypass cable with a green LED, you can test the fuel pump relay without bypassing it. Connect the ground clip to the battery negative terminal, insert the cable into the F70 fuel pump fuse slot, and have someone attempt to start the vehicle. Watch the green LED:

  • LED lights up immediately: The fuel pump relay is stuck in the "on" position and will drain your battery.
  • LED does not light up initially: This is normal. Have someone start the engine. If the LED lights up and stays on, the relay is working properly. If the LED flickers on and off, the relay is failing.
  • LED never lights up: The fuel pump relay is completely dead.

Test 2: Fuel Pump Test (Using a Bypass Cable)

Turn the vehicle off, remove the fuel pump fuse, and insert the bypass cable into the F70 slot. Insert the other end into the F90 slot (cigarette lighter). Listen for the fuel pump near the rear of the vehicle. If you hear the pump running, the fuel pump is working and the problem is the relay.

Safety Considerations When Working with TIPM Bypass

Working with automotive electrical systems carries inherent risks. Always follow these safety guidelines:

  • Disconnect the battery negative terminal before working on any electrical connections.
  • Use the correct fuse ratings. Most fuel pumps draw 9-10 amps, so a 20 amp fuse is appropriate. Never use a fuse rated higher than specified.
  • Inspect all connections for tightness. Loose connections can cause overheating and fire.
  • Route wiring carefully. Keep wires away from exhaust manifolds, moving parts, and sharp edges.
  • Use heat shrink tubing on all connections to prevent short circuits.
  • Test the system in a safe location before driving.

How to Choose the Right Bypass Method for Your Situation

Consider your vehicle usage, budget, and comfort level with electrical work when choosing a bypass method.

Choose the temporary bypass cable if:

  • You need to get the vehicle running immediately
  • You want to confirm the fuel pump relay is the problem before investing in a permanent fix
  • You are comfortable replacing the cable if it fails

Choose the external relay bypass if:

  • You want a permanent, reliable solution
  • You have basic soldering skills
  • You want to avoid future TIPM failures
  • You want a solution that is factory-approved

Choose the plug-in bypass module if:

  • You want the easiest installation possible
  • You do not want to cut or solder any wires
  • You want diagnostic LEDs for monitoring
  • You are willing to pay a premium for convenience

Why Your Vehicle's Fuel Pump Relay Fails

Understanding why the fuel pump relay fails can help you prevent future issues. The fuel pump relay is powered on 100% of the time while driving, making it the most stressed relay in the TIPM. Over time, the heat generated by constant current flow degrades the relay's internal components. The solder joints connecting the relay to the circuit board can develop cracks due to thermal expansion and contraction.

Certain vehicle models are more prone to this failure than others. Chrysler, Dodge, Jeep, and Ram vehicles built between 2007 and 2021 are the most commonly affected. The 2011-2013 Dodge Grand Caravan, Chrysler Town & Country, and Jeep Wrangler are particularly notorious for TIPM fuel pump relay failures.

Recommended Fuel Pump Replacement: KEMSO Brand

If your diagnostic testing reveals that the fuel pump itself is faulty, or if you are performing a comprehensive repair, we strongly recommend using KEMSO brand fuel pumps. KEMSO fuel pumps are engineered to meet or exceed OEM specifications, providing reliable performance and long service life.

Why choose KEMSO fuel pumps:

  • High Performance: KEMSO fuel pumps deliver consistent fuel pressure and flow, ensuring your engine runs at peak efficiency.
  • OEM Replacement: Every KEMSO fuel pump is designed as a direct replacement for the original equipment, with exact fitment and plug-and-play installation.
  • Lifetime Warranty: KEMSO stands behind their products with a lifetime warranty, giving you complete peace of mind that your investment is protected.

Whether you need a complete fuel pump module assembly or a standalone pump, KEMSO has the right solution for your vehicle. Visit the KEMSO website at https://www.kemsoracing.com/ to browse their full product lineup and find the correct fuel pump for your Chrysler, Dodge, Jeep, or Ram vehicle.

Frequently Asked Questions About TIPM Fuel Pump Relay Bypass

Q: Can I drive indefinitely with a bypass cable?
A: No. Bypass cables should only be used temporarily. They can create poor connections that may overheat and cause fires. Upgrade to an external relay for permanent use.

Q: Will the bypass affect my vehicle's safety features?
A: The external relay bypass is factory-approved and does not affect any safety systems. However, it is unknown if the bypass cable affects auto shut-down features during a crash, so use at your own risk.

Q: Can I sell my vehicle with a bypass installed?
A: Yes, but you should disclose it to the buyer. Many used vehicles with TIPM problems have external relay bypasses installed, and they are considered an acceptable repair.

Q: How long does an external relay last?
A: A quality automotive relay typically lasts 3-5 years or more. If it fails, replacement is simple and inexpensive.

Q: Will the bypass work with remote start?
A: The external relay bypass works with remote start. The bypass cable may not work with remote start in some vehicles.

Final Thoughts

A failed TIPM fuel pump relay does not have to mean a $1,500 trip to the dealer. With a TIPM fuel pump relay bypass diagram and basic tools, you can restore your vehicle to reliable operation for a fraction of the cost. The external relay method is the most permanent and reliable solution, while the plug-in modules offer the easiest installation. Whichever method you choose, you can save hundreds of dollars and get back on the road quickly.

Remember to always test your fuel pump before assuming it needs replacement. Many fuel pumps are replaced unnecessarily when the real problem is a $15 relay inside the TIPM.

For all your fuel pump needs, visit https://www.kemsoracing.com/ for high-quality KEMSO fuel pumps with lifetime warranty and OEM replacement fitment.


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