2012 Jeep Grand Cherokee Problems: 32 Known Issues

How to Fix

Record the exact DTCs and freeze-frame data, verify oil level and mechanical oil pressure, and identify whether the sound is from the exhaust manifold or inside the valvetrain. Diagnose ignition and injector causes for the affected cylinder, then perform factory compression and cylinder-leakage testing as indicated. If the evidence remains mechanical, inspect rocker motion, pushrods, lifter rollers, and cam lobes using service information for the exact VIN and engine build. Only after lifter or cam damage is physically confirmed should a technician select the correct mix of deactivating and standard lifters, yokes, camshaft, gaskets, torque-to-yield fasteners, and any contamination-related work. Stop driving and obtain professional diagnosis if the oil-pressure warning appears, the malfunction lamp flashes, severe misfire develops, or metal is found in the oil/filter.

Owner tips & cautions

• WarningDo not buy a camshaft or lifter kit from a tick, a generic misfire code, or the old card's part list. The correct repair depends on physical inspection and the VIN-specific MDS valvetrain configuration.
• TipRule out the exhaust-manifold cold-tick condition first. FCA has a separate crack-inspection path and updated manifold kits for covered 2019-2022 5.7L vehicles.

How to Fix

Replace the affected (left) cylinder head with the updated revised-casting part, including new gaskets and hardware, per TSB 09-002-14. Verify warranty extension X56 coverage (10yr/150k) before paying out of pocket. Diagnose by pulling misfire codes on even-numbered (left-bank) cylinders and performing a leak-down/compression test; confirm the head casting date stamp on used/early engines.

How to Fix

Confirm the misfire is mechanical, not just a coil/plug, via compression or leak-down on the affected left-bank cylinder (TSB threshold: 25%+ leakage). The accepted repair is replacing the failed LEFT cylinder head with the revised casting (hardened valve guides/seats — reman RL141353AC or the updated OEM 'AD' casting), new head gasket and bolts, plus spark plugs and often coils. If the vehicle is within the X56 10-year/150,000-mile window, the dealer replaces the left head at no cost. Independents may rebuild/reseat a head, but the OE remedy is the redesigned head assembly.

Owner tips & cautions

• WarningDo not order a cylinder head from a tick or misfire code alone. FCA requires leakage testing on the cylinder that set the DTC and a result of at least 25 percent before this bulletin's head-replacement path applies.
• TipAsk the dealer to check the VIN for X56 status and repair history even though the original time limit may have expired; coverage was VIN-, time-, and mileage-dependent.

How to Fix

Verify the oil was filled to the correct level and document mileage and oil added under Chrysler's oil-consumption test procedure. If the vehicle passes the test, do not replace PCV parts for this concern. If it fails, inspect the full PCV path for restriction, confirm the installed valve is the correct part for the VIN and engine, and verify the correct intake-vacuum source; repair only a fault found in those checks. If the PCV system is correct, record a cylinder-compression test and perform a leak-down test using the applicable service specifications. Also diagnose any visible external leak separately. Do not order a PCV valve, revised hose, or catch can from oil use alone, and do not treat P052E or P0300 as part of this card without an actual scan and code-specific diagnosis.

Owner tips & cautions

• TipRecord the exact oil level, mileage, and quantity added. A repeatable consumption test is more useful than guessing from one low reading.
• WarningDo not treat the PCV valve as the default repair. Chrysler's sequence checks it only after a failed oil-consumption test and moves to compression and leak-down testing when PCV is correct.
• WarningThe old 30,000-mile PCV interval, catch-can recommendation, P052E/P0300 mapping, and universal valve/hose purchases were removed because the reviewed FCA evidence does not support them for this card.

How to Fix

Before clearing anything, record every PCM DTC, pending code, freeze-frame value, battery voltage, temperature, and the exact conditions under which reduced power occurred. Diagnose prerequisite five-volt-supply, throttle-position, accelerator-pedal, or other active faults in the order specified by the current factory procedure for that VIN and engine. For a P2111-style fault, inspect the throttle plate for binding or foreign material and run the scan-tool throttle-follower test, then test the motor circuits, connector terminals, and wiring as directed. For a pedal-correlation code such as P2138, follow the accelerator-pedal sensor and circuit procedure instead. Replace and relearn a throttle body only when the applicable test condemns it; do not buy a thermostat as an ETC rule-out part.

Owner tips & cautions

• WarningAn ETC lamp does not prove the throttle body failed. Save the codes and freeze-frame data before clearing them or disconnecting the battery.
• TipAsk the shop to name the exact DTC and the failed factory test step before approving any throttle-body, pedal, wiring, or PCM part.

How to Fix

Replace the failed oil filter housing/oil-cooler assembly. The durable accepted fix is an upgraded all-aluminum housing (e.g., Dorman 926-959, earlier 926-876) rather than the failure-prone plastic OE part, with new housing/cooler gaskets and O-rings and fresh oil/coolant. If oil-coolant intermixing occurred, flush the cooling system and change oil. Because the housing sits under the intake manifold, replacement includes intake removal, so shops often do the intake gasket, spark plugs, and a coolant flush at the same time. Housing-only labor+part runs roughly $400-$900, rising with the added items.

Owner tips & cautions

• WarningThe 2011-2013 and 2014 filters are not interchangeable. The two product links are intentionally separated by model year and original factory housing.
• WarningAn aftermarket aluminum housing can change the required filter. Identify that housing and follow its own application instructions instead of ordering from the vehicle year alone.
• TipCompare the new element and supplied O-ring with the parts removed before installation; use only the seal included with the correct filter.

How to Fix

Inspect the engine mounts for fluid weepage and separated rubber; wet/leaking hydraulic mounts should be replaced (replace in pairs on higher-mileage trucks and inspect the transmission mount at the same time). Use OEM Mopar hydraulic mounts rather than solid rubber aftermarket units, which reintroduce vibration. Re-verify idle smoothness in gear after replacement and confirm the driveshaft/mounts aren't jointly contributing.

How to Fix

Clean the area and add approved oil dye so the source can be observed before parts are ordered. Inspect the oil-filter-cap O-ring for damage and confirm it is seated in the correct groove. Check the five oil-filter-adapter bolts against FCA's 12 N-m specification and document any under-torque condition. If dye confirms a leak at the adapter-to-block interface, follow the current VIN- and model-year-specific FCA service information: the cited guidance calls for O-ring/gasket kit 68191356A$ rather than a complete adapter on covered vehicles other than model year 2014, and calls for adapter replacement on model year 2014. Transfer sensors only when the applicable replacement procedure requires it. Verify the exact suffix and current part by VIN before ordering. Do not buy a housing, cooler, seal kit, or aluminum conversion until the leak source and installed housing are confirmed.

Owner tips & cautions

• TipAsk the shop to show the dye-confirmed source: cap O-ring, adapter bolts, or the adapter-to-block interface. Those paths do not all require the same part.
• WarningDo not authorize a complete housing from oil in the valley alone. FCA specifically directs seal-only repair for a confirmed interface leak on covered non-2014 vehicles.
• WarningModel year 2014 is an exception in FCA's cited guidance. Confirm the VIN, model year, leak source, and current part suffix before ordering anything.

How to Fix

Use quality synthetic oil meeting Chrysler MS-6395 spec. Consider MDS delete kit for permanent solution. Some owners have replaced lifters and camshaft under extended warranty. Regular oil changes help minimize tick progression.

Owner tips & cautions

• TipRegular oil changes help minimize tick progression.
• TipGet a proper diagnosis before replacing parts - similar symptoms can have different causes

How to Fix

Clean the area and use UV dye to pinpoint the source before disassembly. For an upper oil-pan gasket leak, replace the upper pan gasket (significant labor). For an oil-pressure sensor leak, replace the sensor under the intake manifold. Rule out the oil cooler/filter housing (a separate known leak) so the correct part is fixed the first time.

Owner tips & cautions

• WarningP0520 is a sensor-circuit code. Do not describe it as proof of an oil leak or actual low mechanical oil pressure without the required diagnosis.
• TipConfirm the March 12, 2014 build cutoff and exact DTC before ordering. The FCA service action is narrower than the old 2011-2021 card.
• WarningThe linked sensor is the exact 05149062AA named by FCA. The required intake seals are listed without retailer links until exact product pages and current VIN supersessions are verified.

How to Fix

For fuel pump relay failure: Install an external bypass relay kit ($30-50 DIY) to power fuel pump directly. For complete fix: Replace TIPM unit with remanufactured unit ($400-600) or new OEM ($800-1,200). Some electrical shops can repair/rebuild existing TIPM for $200-400.

Owner tips & cautions

• WarningThis is a high-severity issue - ignoring it can lead to costly repairs or safety concerns. Address it promptly.
• TipConsider OEM parts for critical components like sensors and electrical parts - aftermarket can be unreliable
• TipGet a proper diagnosis before replacing parts - similar symptoms can have different causes

How to Fix

Check the VIN for open P60 / 14V-634 and T36 / 17V-435 campaigns and schedule an authorized Jeep dealer if either is incomplete. FCA's T36 procedure has the dealer inspect the alternator part-number tag; a listed improved unit needs no further action, while a suspect, illegible, missing, aftermarket, or remanufactured unit is replaced under the campaign with an alternator containing improved diodes. The recall repair is free for an eligible VIN, and the owner notices include a reimbursement path for qualifying prior repairs. Do not use the old retail alternator, battery, starter, charger, or EV-charger links in place of the recall. If the vehicle loses electrical power, stalls, or shows alternator heat, smoke, or fire, stop safely, move occupants away, and arrange towing or emergency assistance as appropriate.

Owner tips & cautions

• WarningRecall eligibility is VIN-specific. Check both P60 / 14V-634 and T36 / 17V-435; do not assume a prior generic alternator replacement completed the campaign.
• TipFCA's T36 process starts with the alternator tag. The dealer replaces the unit only when the tag/part status calls for it, and an illegible, missing, aftermarket, or remanufactured unit is handled under the campaign procedure for an eligible VIN.

How to Fix

Have the applicable recall performed (NHTSA 14V-634 for 160-amp 3.6L units, and 17V-435 for EHPS-equipped 5.7L/3.6L vehicles): dealers inspect and replace the alternator free of charge. Out of warranty, replace the alternator with an updated unit; budget roughly $400-$700 including labor.

How to Fix

For dim/aged output replace the HID bulbs (and ballast if a bulb fails to strike); match bulbs in pairs for even color. For mechanical high/low projector faults inspect the projector shutter solenoid. If condensation does not clear after running the lights, replace the headlight assembly due to a failed seal. Restore hazed lenses or replace assemblies as needed.

How to Fix

Scan for transmission codes; for limp mode inspect/replace the conductor plate (with integrated speed sensors) and any failed shift solenoid, and replace the 13-pin connector adapter/seal if leaking. Perform a full fluid-and-filter service with the correct ATF (MB 236.x / Mopar spec). Address water intrusion at the fill tube. Severe internal damage from prolonged shudder may require a rebuild.

How to Fix

Confirm the vehicle is equipped with Quadra-Lift sales code SER, record the exact ASCM DTCs and environmental data, and check VIN/build-date-specific FCA bulletins before ordering hardware. Follow the factory sequence: repair voltage or communication faults first; inspect fuses, air lines, springs, height-sensor linkages, compressor intake/filter, and visible plumbing; then use a capable scan tool to run the Air Mass and Air Ride Height routines and follow the DTC-specific tree. On 2011-2012 vehicles built before May 1, 2012, U0415-00 or C159E-15 with a Service Air Suspension message may be addressed by FCA TSB 08-034-12's ASCM software update. Replace only the component proven failed. A completely depleted system requires the specified refill equipment, scan-tool procedure, and purity-class-5 nitrogen; do not fill it with ordinary shop air or shotgun-replace springs, sensors, and the compressor.

Owner tips & cautions

• WarningDo not replace a compressor because the vehicle sits low. A leaking spring or line, sensor/linkage fault, intake restriction, valve fault, low system air mass, or software condition can create overlapping symptoms and can overwork a replacement compressor.
• TipAsk the shop to record the ASCM DTCs, air-mass result, ride-height routine result, and verified leak location. Those findings should select the part, not a generic model-level shopping list.

How to Fix

Record when the noise occurs and reproduce it safely on a controlled road test. With the vehicle supported according to the factory procedure, inspect wheel and tire security, brake hardware, steering linkage, stabilizer links and bushings, control-arm bushings, upper and lower ball joints, shocks and mounts, wheel bearings, subframe attachment, and nearby shields or loose hardware. Check joints and bushings in the loaded and unloaded positions specified by the service manual, and use chassis ears or controlled isolation when visual play is not obvious. If steering looseness, wheel movement, instability, or a damaged joint is present, stop driving until repaired. Replace only the confirmed failed component using the VIN, side, suspension sales code, and current supersession; torque at the specified ride-height condition and perform an alignment when the repair procedure requires it.

Owner tips & cautions

• WarningDo not assume a sway-bar link or control arm from the sound alone. Steering looseness, wheel movement, or a damaged ball joint requires immediate inspection before more driving.
• TipAsk the shop to identify the exact failed joint or bushing, side, and suspension sales code and to show the measured play or isolated noise before parts are ordered.

How to Fix

Confirm the failing corner by listening for the speed-dependent hum and checking for bearing play; the noise typically worsens when turning toward the good side. Replace the affected front hub/bearing assembly (sold as a complete unit). Replacing in pairs is common when both have similar mileage. Verify ABS sensor function after replacement.

How to Fix

Inspect the front and rear diff pinion flanges and transfer-case output for gear-oil weepage; confirm fluid level. Replace the leaking pinion seal, marking pinion-nut position/turns to preserve preload (or setting new preload with a fresh crush sleeve) to avoid bearing damage. If gear whine is already present from prior low-lube running, evaluate the ring/pinion and bearings and refill with the correct spec gear oil. Address any transfer-case seal leaks at the same time.

How to Fix

Diagnose by roadtest and by inspecting the rear propshaft: clean redistributed grease out of the slip-joint boot and re-grease the slip yoke, check CV joints for play/binding, and verify driveshaft/pinion angles and center bearing condition. Rebalance or replace the rear driveshaft assembly if joints are worn. Confirm engine and transmission mounts are not collapsed (a frequent contributor). Replacing a worn rear driveshaft or reconditioning the slip joint typically resolves it.

How to Fix

Scan for transfer-case actuator/control codes (e.g., C140F) before parts replacement. The shift motor is accessible after removing the belly skid guards (four bolts and a connector) and is the first replacement; if the fault persists, test the transfer case control module and wiring, and inspect the actuator's internal encoder ring/case for damage before condemning the whole transfer case. Verify any applicable recall coverage tied to the fault code.

How to Fix

Replace water pump when symptoms appear or preventatively during timing chain service. Replace thermostat at same time. Consider replacing timing chain tensioners and guides if high mileage. Ensure proper cooling system bleeding after repair.

Owner tips & cautions

• TipReplace water pump when symptoms appear or preventatively during timing chain service.
• TipGet a proper diagnosis before replacing parts - similar symptoms can have different causes
• TipSearch Jeep Grand Cherokee forums and owner groups for real-world experiences and DIY guides
• TipGet multiple quotes from independent mechanics - dealer prices can be 2-3x higher for the same repair

How to Fix

Replace the thermostat (integrated into the Mopar thermostat housing, e.g. 5184651AH-family for 3.6L) using an OEM-grade unit, then properly bleed all air from the cooling system via the bleeder. Verify the coolant temperature sensor and confirm correct coolant level before condemning the thermostat. Clear P0128 and confirm the engine reaches full temp over a few drive cycles.

How to Fix

Perform a dye or electronic leak test to confirm the condenser as the leak point. A leaking condenser cannot be repaired and must be replaced, followed by an evacuation, vacuum, and recharge with the correct refrigerant/oil. Replace the receiver/drier as part of the job. Address any debris damage to prevent recurrence.

Owner tips & cautions

• WarningDo not buy a condenser because the A/C is warm or because a recharge leaked down. The exact leak location and any separate control or air-door fault must be proven first.
• WarningAvoid stop-leak products. FCA warns they can contaminate the system and damage recovery, evacuation, and charging equipment.

How to Fix

Confirm the diagnosis: sweet smell + foggy windshield + wet passenger carpet = leaking core; cold-only output with good coolant flow points to a clogged core (attempt a back-flush first). Pressure-test the cooling system and inspect the plastic heater pipes/elbows at the firewall, which can be replaced separately if that's the leak point. If the core itself leaks or is clogged, replace the heater core (dash-out labor). Refill and bleed the cooling system afterward and verify heat and no coolant loss.

How to Fix

Clear the front and rear drain tubes with low-pressure compressed air or a flexible line (avoid high pressure, which can pop the tube off the roof). Re-seat or replace cracked/disconnected tubes; some require partial headliner removal. Dry the carpet/underlayment fully to prevent mold and protect floor electronics.

How to Fix

Dry the accessible area enough to see a new water track, protect affected electrical connectors and modules, and reproduce the conditions under which the leak occurs. Follow the factory water-leak procedure: visually inspect plugs, drains, alignment, seams, seals, and grommets; test one region at a time with an appropriate low-pressure stream or fan spray; remove trim only as needed for safe visual access; and trace the highest fresh water track to its actual entry point. Repair, reseat, or replace only the confirmed failed seal, seam, fastener, drain, weatherstrip, glass bond, lamp seal, or wiring pass-through using the current factory procedure and specified material. Dry wet insulation, inspect exposed terminals for corrosion, and repeat the water test before closing the trim. Do not smear generic RTV across several unconfirmed paths.

Owner tips & cautions

• WarningThe puddle location may not be the entry location. Do not buy a grommet, weatherstrip, sealant, or lamp seal until a controlled water test identifies the source.
• TipPhotograph the first fresh water track during the test and retest after the repair before reinstalling all wet trim and insulation.

How to Fix

Scan for P2068/P0461/P0463 and confirm which sender is faulty. Inspect the sender for a stuck float and check connector/wiring; some intermittent stuck floats free up, but a failed sender requires replacement of the affected fuel-level sensor/sender module (often the in-tank pump/sender assembly), which typically means lowering the fuel tank. Recalibrate/verify gauge sweep after repair.

How to Fix

Inspect the capless filler neck flapper and internal check valve; clean debris and verify the flapper closes/seals. If it sticks or the nozzle keeps clicking off, replace the capless fuel filler neck with the latest revised part. As a temporary field workaround owners report inserting the nozzle more slowly (or gently holding the flapper open) — but the durable fix is filler-neck replacement. Rule out a plugged EVAP/vent restriction if fill problems persist after replacement.

Owner tips & cautions

• WarningDo not order by the symptom alone. FCA requires the other hard-to-fill diagnostics first, and the correct tube changes with engine sales code and model year.
• TipHave the seller or installer verify the VIN, engine sales code, and current Mopar supersession before the order is placed.

How to Fix

Diagnose before replacing parts. (1) Inspect/re-tighten or replace the gas cap and confirm it clicks and seals — rule out the cheapest cause first. (2) Visually inspect the thin plastic EVAP purge-valve hose on top of the engine for cracks/splits (especially at connection points) per TSB #25-002-15 REV-B; replace if brittle/cracked — this alone fixes many cases. (3) Locate the ESIM/leak detection pump (on the charcoal canister near the rear driver-side wheel well); remove and shake it — if it rattles, the internal valve has failed and the module must be replaced. Replacement is a straightforward DIY: a new ESIM (OEM, or aftermarket such as Dorman 310-219) installs in place of the old one. After replacement, clear the codes and complete a few drive/fill cycles to confirm the EVAP monitor passes and the light stays off. If codes persist after ESIM and hose service, smoke-test the EVAP system to find a remaining leak (canister, lines, or fuel-tank-side seals).

Owner tips & cautions

• WarningP0455/P0456 does not identify an ESIM, gas cap, canister, or hose by itself. Match the build window and inspect or smoke-test the system before buying a part.
• TipUse the VIN and engine sales code to distinguish the 3.6L and 5.7L purge hoses before ordering.

How to Fix

Start with a new OEM Mopar gas cap and confirm it clicks/seals; clear the code and drive several cycles. If it returns, replace the ESIM in the rear driver-side wheel well (accessed behind the fender liner, on the charcoal canister). If still present, smoke-test the EVAP system to find hose/purge-valve/canister leaks.

How to Fix

There is no preventive repair — the panel must be replaced with new tempered glass (dealer or auto-glass shop), and owners should verify the sunroof frame/track and drains are correct so the replacement isn't re-stressed. Document the event and file an NHTSA complaint (helps trigger any future investigation/coverage) and check comprehensive insurance, which often covers glass with low/no deductible. Retain any FCA/Stellantis goodwill-assistance option for low-mileage vehicles.