Two problems that get confused
6.7 Cummins Grid Heater Problems
Owners often blend the intake-grid fastener concern, heater circuit codes and the official relay recall into one issue. They are related to the same cold-start system but require different checks.
Aftermarket-documented concern
Grid fastener loosening
Diesel specialists and owners have documented a grid-heater fastener loosening and potentially entering the intake. Frequency is debated, so avoid declaring every truck defective; unusual noise, a loose connection or related codes deserve professional inspection.
Official safety action
Grid-heater relay recall
Certain trucks have been recalled for a solid-state intake-grid relay that can short and create an engine-compartment fire risk. This is VIN-specific and separate from the fastener discussion.
What to do when a code appears
- 1.Record every code and freeze-frame condition before clearing anything.
- 2.Check the VIN for open Ram and Transport Canada recalls.
- 3.Inspect the relay, high-current cable and grid connection for overheating only with the batteries safely isolated and the proper service procedure.
- 4.For P2609 or P0542, use current service information rather than replacing a relay from the code name alone.
- 5.If a fastener is suspected loose or missing, stop repeated starting and have the intake inspected before debris can travel farther.
Grid heater vs block heater
The grid heater warms intake air during starting. The Ram block heater warms the engine before starting. In deep Canadian cold they complement each other; one is not a direct substitute for the other.
Cold-start equipment for Cummins owners
Amazon buying options
Kat's 13150 circulating tank heater, 1,500 W
Plumbs into a heater hose and thermosiphons hot coolant through the whole engine — the serious option for big diesels, tractors, and equipment with no frost-plug access.
Confirm the exact specification and application in the listing before ordering.
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Amazon buying options
NOCO Boost GB150 lithium jump starter, 3000 A
The pro-grade boost pack — rated for gas engines to 9 L and diesels to 7 L. What actually turns over a cold Cummins or DT466 when the batteries give up.
Confirm the exact specification and application in the listing before ordering.
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Amazon buying options
Howes Diesel Treat anti-gel, 64 oz
The trucker-standard winter conditioner — prevents gelling, adds lubricity, no alcohol. The 64 oz jug treats hundreds of litres; dose every fill from November on.
Confirm the exact specification and application in the listing before ordering.
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Quick questions
Is the 6.7 Cummins grid-heater bolt covered by a recall?
Do not confuse the widely discussed intake-grid fastener concern with the official grid-heater relay recalls. Recall eligibility is VIN-specific; check the current Ram or Transport Canada recall lookup.
What do P2609 and P0542 mean?
They concern intake-air-heater performance or circuit operation. A 2016 FCA technical tip for certain 2012–2016 6.7L trucks instructed technicians to replace the grid and relay together and inspect the cable for overheating.
Should Canadians delete the grid heater?
A simple delete sacrifices a designed cold-start aid. In a Canadian climate, discuss a verified replacement or engineered alternative with a qualified diesel technician rather than treating removal as the default.
Primary references: FCA 2016 grid/relay technical tip · 2023 relay recall notice. Context on the fastener concern: Banks Power history; treat commercial claims as aftermarket evidence, not a recall determination.