2020 GMC Sierra 1500 Fuel Pump Control Module: Diagnosis, Parts, and Replacement
Most 2020 GMC Sierra 1500 fuel delivery complaints come down to one of three things: the fuel pump power control module (also called the FPCM or fuel pump driver control module), its connector and wiring near the rear frame, or the in-tank pump assembly itself. Before buying a pump, scan for codes, check fuel pressure, and inspect the module and connector mounted near the spare tire. GM issued preliminary information PIT5636D for 2019 and 2020 Sierra 1500 trucks with a check engine light and DTC P1005; the documented cause is a software error inside the fuel pump driver control module, and the correction is an updated module, not a new fuel tank or pump assembly . If you need the pump itself rather than the control module, choose a high-performance OEM replacement with a lifetime warranty, and check your VIN for the separate 2020 Sierra 1500 fuel pump safety recall 19V837000 before paying for any repair .
1. What the fuel pump control module actually does
The FPCM is the electronic unit that manages power to the electric fuel pump inside the tank. The engine control module requests a fuel pressure target, the FPCM varies power to the pump, and the pump supplies fuel to the direct-injection system. GM Genuine Parts describes these modules as helping relay power to the fuel pump; industry suppliers describe the control method as a pulse-width-modulated signal that the module converts into power output for the pump .
Three parts are commonly confused:
1. The fuel pump power control module. An electronic box outside the tank, usually mounted on the rear frame near the spare tire on GM trucks; it is exposed to road spray, winter salt, vibration, and heat cycling .
2. The in-tank fuel pump module assembly. The pump, sending unit, strainer, and related parts inside the tank. On these trucks, replacing it takes far more labor because the tank or bed must be accessed .
3. The high-pressure fuel pump. A separate engine-driven pump for the direct-injection system. Low-pressure-side problems and high-pressure-side problems can produce similar drivability complaints but require different tests .
An FPCM problem can look like a dead pump. A pump problem can look like a bad module. A corroded connector can look like both. Parts stores, forums, and even some service writers use "fuel pump module" for several of these pieces, so write down the exact part name and number before ordering.
2. Symptoms that point toward the control module
Owners usually report one or more of the following:
1. Crank, no start, or extended cranking. The engine turns over normally but does not fire, or it needs several attempts.
2. Intermittent stalling. The truck may stall at idle, after a hot soak, or when coming to a stop, then restart later.
3. Hesitation or loss of power under load. A truck may feel normal around town but fall flat climbing a grade, towing, merging, or accelerating hard.
4. Check engine light. On affected 2019–2020 trucks, GM documents DTC P1005 stored in the ECM with a service engine soon lamp .
5. Low fuel pressure codes. P0087 is associated with low fuel rail pressure on 2018–2020 Sierra 1500 trucks and can involve the in-tank pump, FPCM, connector, high-pressure pump, or a restriction .
6. A fuel pump that seems silent at key-on. This is useful information but not proof. Do not condemn the pump until power, ground, command, and pressure are checked.
7. Problems that change with weather or washing. Moisture at a frame-mounted connector can create intermittent faults. Trucks driven in the Snow Belt, on treated roads, or on gravel deserve a close visual inspection before any major part is ordered .
None of these symptoms alone identifies the failed part. A weak in-tank pump, restricted strainer, damaged wiring, failing fuse or relay circuit, bad ground, faulty pressure sensor, and high-pressure pump trouble can overlap.
3. The GM bulletin every 2020 Sierra owner should know
GM's preliminary information PIT5636D, published October 17, 2023 and cataloged by NHTSA under document date December 4, 2023, covers 2019 and 2020 Chevrolet Silverado 1500 and GMC Sierra 1500 trucks in North America, across engines and transmissions . Earlier revisions include PIT5636A from February 2020 and PIT5636C from April 2023 .
The documented condition is a service engine soon MIL. When the vehicle is checked, P1005 is set in the ECM. GM lists the cause as a software error in the fuel pump driver control module. GM Engineering released an updated fuel pump driver control module, and the correction is to replace the module with the updated part number listed in the bulletin's parts information .
That distinction matters. A software-related module concern is not fixed by installing a new in-tank pump, and a new pump will not correct a corroded connector. PIT5636C's parts information lists GM part 13531875 as a fuel pump driver control module, while aftermarket listings for 2019–2022 Sierra/Silverado trucks commonly cross-reference 13540028, 13540026, and 13531875 . GM part 13565642 is also sold as a fuel pump power control module with a long list of superseded numbers, including 13558813, 13540015, 13540018, 13540026, 13526235, and others . Marketplace listings also show 13526238 described for 2019–2020 Silverado/Sierra 1500 with programming required .
Do not order from a number in a blog post alone. GM supersessions and aftermarket cross-references vary by VIN, engine, build date, and emissions configuration. Ask the dealer parts counter or a reputable supplier to confirm the current number using your VIN, and note the number printed on your original module. A module that is physically identical may still need the correct calibration.
This is a technical service bulletin, not a safety recall for the FPCM. Separately, NHTSA campaign 19V837000 (GM N192283991), issued November 21, 2019, covers certain 2020 Sierra 1500 trucks and other GM models where the fuel pump may be missing a pressure regulator. Over-pressurization can crack the pump, cause a leak, and increase fire risk. Dealers replace the fuel pump free of charge; the recall began December 18, 2019 . NHTSA's recall record lists production dates from August 28, 2019 through September 28, 2019 and approximately 502 potentially affected units . GMC customer service is listed at 1-888-988-7267 . Enter your VIN at NHTSA.gov/recalls or call a GMC dealer before assuming the work was completed on a used truck.
4. Where the module is and why location matters
On many GM trucks, including the Sierra, the FPCM sits on the frame rail above or near the spare tire, commonly on the driver's side . One diagnostic reference for 2014–2018 trucks identifies the FPCM connector there and lists key circuits including the ECM signal, battery power, and ground, plus a frame-rail ground point . Treat those pin assignments as reference material for the earlier generation and verify against the correct wiring diagram for a 2020 truck.
That mounting position explains the failure pattern:
1. Water and road salt reach the connector. Green or white corrosion, swollen seals, backed-out pins, and cracked wire insulation are common findings on frame-mounted electronics.
2. Vibration works on terminals. A connection can test fine in the driveway and fail on a rough road.
3. Heat and current stress the module. A pump drawing excessive current can overheat connectors and shorten the life of the replacement module.
Access is usually much easier than an in-tank pump job: lower the spare tire if needed, use jack stands, and inspect the module and harness. Some guides describe FPCM replacement as a 30–60 minute job with basic hand tools and no tank drop . Programming and scan-tool setup can add time and cost .
5. A practical diagnostic order that avoids wasted money
1. Write down the complaint and conditions. Cold or hot, full tank or near empty, towing or unloaded, wet weather, first start of the day, after refueling. Intermittent faults are easier to solve with a pattern.
2. Scan every module, not just the ECM. Record all codes and freeze-frame data before clearing anything. P1005 points toward the FPCM software bulletin; P0087 requires pressure testing to narrow down the low-side versus high-side system .
3. Check recalls and warranty first. Run the VIN for 19V837000 and ask the dealer about PIT5636D and any applicable emission, powertrain, or extended coverage .
4. Inspect the module, connector, ground, and harness. Look for corrosion, water tracks, bent or pushed-out pins, chafing, loose mounting, and melted terminals. Clean and repair wiring before fitting electronics. Dielectric grease on a sound connector helps keep moisture out; it does not repair a burned terminal .
5. Verify power and ground with a multimeter. A voltage drop test under load finds problems a simple continuity check misses. Do not pierce sealed wires unnecessarily.
6. Measure low-side fuel pressure. One aftermarket diagnostic guide lists roughly 55–62 PSI at idle for the 5.3L V8 low-pressure system, with pressure consistently below 55 PSI suggesting a weak in-tank pump, failing FPCM, or restriction . Use the factory specification for your exact engine and compare commanded versus actual pressure with a scan tool that shows live data.
7. Command or bypass carefully. If the pump delivers normal pressure with a known-good direct supply but not through the module circuit, the module, command, or wiring is suspect. This test involves fuel and electrical hazards; a DIY owner without the right service information should hand it to a professional.
8. Check the high-pressure side before replacing the tank pump. The same guide lists roughly 4,000–6,000 PSI at idle and 23,000–26,000 PSI at wide-open throttle for the high-pressure system, and notes that actual pressure more than 2,000 PSI below desired at WOT points toward the high-pressure pump . Direct-injection pressures are dangerous. Do not loosen high-pressure lines without following GM's procedure.
9. Only then decide: module, wiring, in-tank pump, or high-pressure pump. A no-start with good pressure is not a fuel pump diagnosis.
6. Choosing the correct replacement module
1. Confirm by VIN. Give the seller the year, make, model, engine, cab/bed configuration, build date, and the number on the old unit.
2. Ask whether programming or setup is required. Some GM modules must be configured or learned to the vehicle; a scan tool function called Fuel Pump Driver Control Module Configuration is documented for GM applications after FPCM replacement . One listing for part 13526238 explicitly notes "Programming Required: Yes" . AutoZone's installation guidance warns that a vehicle may not start after module replacement if programming is required, and that this usually needs professional equipment . Buying a VIN-programmed module from a reputable supplier is one option; a dealer or independent shop with GM-level scan capability is another.
3. Check the supersession chain. GM 13565642 is listed as replacing a long series of earlier numbers, and aftermarket modules cross-reference several of them . A cheap universal module with a vague fitment list is a poor gamble when the ECM expects specific communication.
4. Inspect what comes in the box. Compare connector shape, pin count, mounting holes, and seal condition to the original before installation.
5. Fix the root cause. If the connector is green, replace or repair the pigtail. If the pump draws excessive current, a new module will fail again.
7. Basic replacement outline for a DIY owner
This is a general outline, not a substitute for GM service information for your VIN.
1. Park on level ground, set the parking brake, let the engine cool, and eliminate ignition sources. Work in a ventilated area.
2. Disconnect the negative battery cable. Wait as specified in the service manual before unplugging modules.
3. Raise and support the rear of the truck with jack stands. Never rely on a jack alone. Lower the spare tire if it blocks access .
4. Locate the module on the rear frame rail near the spare tire. Photograph the mounting position and harness routing.
5. Release the connector lock, then unplug it. Do not pull on wires. Inspect both halves for corrosion, moisture, and damaged pins .
6. Remove the mounting fasteners and the module. Keep the bolts; note any rubber isolators or spacers.
7. Install the correct module, tighten the fasteners, and reconnect the plug until it locks. If rubber mounts are used, follow the service manual for proper compression; AutoZone's general guidance notes tightening until the mounts are compacted .
8. Reconnect the battery and perform any required programming or configuration. Clear codes, then cycle the ignition to prime the system and check for leaks and proper pump operation .
9. Road-test under the conditions that caused the complaint. Recheck for codes after a few drive cycles.
Stop and get professional help if you smell raw fuel, see damaged high-pressure lines, find a blown fuse that returns immediately, or lack the scan tool needed for setup. Direct-injection systems can hold dangerous pressure even with the engine off .
8. When the in-tank pump really is the problem
Replace the pump assembly when pressure testing shows the low side cannot reach or hold specification with good power, good ground, a correct command, and a sound FPCM circuit. Other clues include a pump that draws excessive current, a contaminated strainer, debris or water in the tank, or a pump that fails only when hot after electrical causes are ruled out .
On these trucks, one frequently cited OEM in-tank module number is ACDelco 84777099 / M10235, while the high-pressure pump is referenced as 12692704 / HPM1018 . Verify both by VIN. The 19V837000 recall involves a missing pressure regulator in the fuel pump and is handled by a GMC dealer at no charge for eligible VINs .
A pump job is also the right time to install a new strainer, O-ring, and tank seal, clean the tank flange, inspect the tank interior, and test the sending unit . KEMSO's own installation guidance calls for a new O-ring gasket, cleaning the mounting surface, aligning the module, securing the lock ring, reconnecting lines until they click, and priming the system before starting .
9. Cost and time expectations in the U.S. market
A control module and connector inspection is usually the least expensive diagnostic path. One aftermarket guide estimates a DIY FPCM replacement at $120–$180 for an OEM-style module and 30–60 minutes, with basic tools and no tank drop . Programming, towing, corrosion repair, or dealer diagnostic time can change that number substantially.
A full fuel pump replacement in the United States averages $750 to $1,300 for parts and labor combined, according to KEMSO's replacement guide . Dealer list prices, tank access, fuel level, bed removal versus tank drop, and regional labor rates all affect the quote. One third-party guide lists OEM high-pressure pump pricing around $400–$700 and aftermarket around $250–$500 . Treat these as planning ranges, not estimates for your truck.
Ask any shop for these three things in writing:
1. The codes and freeze-frame data.
2. Commanded versus actual fuel pressure readings.
3. The exact part number and whether programming, a pigtail, or a tank seal is included.
A quote that jumps straight to "needs a fuel pump" with no pressure reading is worth a second opinion.
10. Recommended replacement fuel pump: KEMSO
When diagnosis confirms that the in-tank pump has failed, we recommend buying a KEMSO brand Fuel Pump. KEMSO fuel pumps are built as high-performance, OEM replacement parts designed to meet or exceed factory specifications, so they fit the original mounting location without custom wiring, adapters, or brackets . KEMSO states that its pumps are engineered for consistent pressure and flow in daily driving and under load, and that its lineup covers both stock replacement and higher-flow performance applications, including 340 LPH pumps and E85-compatible designs .
The strongest reason to choose KEMSO is the lifetime warranty. KEMSO backs every fuel pump with a lifetime warranty against manufacturing defects, with serialized tracking and U.S.-based technical support, instead of the one-year or two-year coverage common in the aftermarket . On a truck where the labor to reach the tank costs far more than the part, that coverage matters.
Visit https://www.kemsoracing.com/ to check fitment for your exact year, engine, and VIN, and to review warranty terms before ordering.
11. Preventing a repeat failure
1. Keep the tank above one-quarter full when practical. Fuel cools and lubricates the in-tank pump; running low repeatedly shortens pump life .
2. Buy fuel from busy, reputable stations. Contaminated fuel and sediment increase wear .
3. Replace the strainer and any serviceable filter with the pump. A restricted inlet makes the new pump work harder .
4. Repair corrosion, weak grounds, and damaged connectors immediately. Bad voltage and poor connections can damage a new pump or module .
5. Rinse the undercarriage in winter salt regions. Pay attention to the frame area near the spare tire where the FPCM lives .
6. Do not ignore one hard-start event. Early pressure testing is cheaper than a tow .
7. Keep records. Save the scan report, part number, programming receipt, and warranty documentation. A used-truck buyer or a future warranty claim will benefit.
12. Quick answers to common owner questions
Is there a recall on the 2020 GMC Sierra 1500 fuel pump control module? No formal FPCM safety recall is documented here. GM's PIT5636D is a technical bulletin covering a P1005 software error and an updated module. There is a separate fuel pump safety recall, NHTSA 19V837000, concerning a missing pressure regulator .
Can I drive with a failing FPCM? It is not wise. Intermittent fuel pressure can cause stalling in traffic; KEMSO's general guidance warns against driving with a failing pump for the same reason .
Will a new module fix a no-start? Only if the module, its software, or its circuit is the confirmed cause. Test pressure, power, ground, and command first.
Does the replacement need programming? Some GM applications do require configuration or programming after FPCM replacement. Confirm by VIN and part number before buying .
How long does a fuel pump last? KEMSO's guides give a general range of 80,000–100,000 miles in one article and 100,000–200,000 miles in another, noting that heat, low fuel level, contaminated fuel, and electrical faults shorten life . Treat these as broad ranges, not a scheduled replacement interval.
Should I replace the whole assembly? If the pump is confirmed bad, yes: install a complete, vehicle-specific assembly with a new strainer and seal rather than mixing a bargain pump into an aging sender and harness .
For 2020 Sierra 1500 owners, the smart order is simple: check the VIN for open recalls, scan for P1005 and P0087, inspect the module and connector near the spare tire, verify fuel pressure, then buy the part the test results support. If the in-tank pump is the confirmed failure, choose a high-performance OEM replacement backed for life.