Trailer Brake Controllers
Tekonsha Prodigy P3 vs Primus IQ
Same braking principle, different amount of information. Whether that is worth the difference depends on how many trailers you own.
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Short answer
Both brake proportionally and both stop a trailer properly. The P3 adds per-trailer memory, boost settings and diagnostics that name faults. If you tow one trailer behind one truck, the Primus IQ does the job.
What the P3 adds
- Per-trailer memory. Stores gain settings for multiple trailers. The practical value is not convenience, it is that you cannot drive off with the gain set for a different trailer.
- Boost settings. Bias output toward the trailer earlier in the stop, which is useful on a heavy trailer or a long descent.
- Diagnostics. On-screen messages identifying what is wrong, instead of an indicator refusing to light.
- A larger display. Trivial until you are trying to read it in daylight.
What the Primus IQ keeps
Proportional braking, a manual override, gain adjustment, and a compact body that fits where a bigger controller will not. That is the functional core, and none of it is compromised to hit the lower price.
Quick picks
Tap any row to jump to the full write-up. How these are chosen - and what we do and do not claim to know - is published in full on our research methodology page.
| # | Product | Best for | Our read | Price |
|---|---|---|---|---|
| 1 |  Tekonsha Prodigy P3 Trailer Brake Controller If you tow several trailers | Towing more than one trailer | Memory, boost and on-screen diagnostics | Check price on Amazon #ad Affiliate link - we publish no price; Amazon shows the current one |
| 2 |  Tekonsha Primus IQ Trailer Brake Controller If you tow one | One truck, one trailer | The same proportional braking, less to read | Check price on Amazon #ad Affiliate link - we publish no price; Amazon shows the current one |
1. If you tow several trailers
Tekonsha Prodigy P3 Trailer Brake Controller
Tekonsha · Best for towing more than one trailer
The proportional controller most other proportional controllers get measured against. It stores settings per trailer, reads out what it is actually doing, and diagnoses wiring faults on the screen instead of leaving you guessing at the connector.
We have not sourced a full specification table for this model from the manufacturer’s own site at a stable address. Rather than repeat figures we cannot cite, the assessment above is limited to what the design and the maker’s published description genuinely establish.
What works
- Stores separate settings for multiple trailers, so you are not re-dialing gain every trip
- On-screen diagnostics name the fault instead of just refusing to work
- Boost settings let you bias braking toward the trailer on a heavy load
What does not
- Needs a proper mounting location within reach and sight of the driver
- More controller than a single light trailer ever needs
Skip it if
Overkill if you tow one small trailer a few times a year and never change the load - a simpler proportional unit does the same job on that trip.
#ad Affiliate link - we publish no price; Amazon shows the current one
2. If you tow one
Tekonsha Primus IQ Trailer Brake Controller
Tekonsha · Best for one truck, one trailer
Proportional braking without the memory, the boost profiles or the big display. For one truck and one trailer, that subtraction costs you almost nothing in how the rig actually stops, which is why it stays the default recommendation for a first controller.
We have not sourced a full specification table for this model from the manufacturer’s own site at a stable address. Rather than repeat figures we cannot cite, the assessment above is limited to what the design and the maker’s published description genuinely establish.
What works
- Proportional response at a far lower price than a flagship controller
- Small enough to mount where a larger unit will not fit
- Mounts at a range of angles without needing to be level
What does not
- No per-trailer memory, so a second trailer means re-setting gain each time
- Display tells you much less when something is wrong
Skip it if
Not the one if you swap between a light utility trailer and a heavy camper - without stored settings you will eventually drive off on the wrong gain.
#ad Affiliate link - we publish no price; Amazon shows the current one
| Situation | Pick |
|---|---|
| One trailer, one truck, consistent load | Primus IQ |
| A camper and a utility trailer | Prodigy P3 - memory prevents a wrong-gain departure |
| Mountain towing with a heavy trailer | Prodigy P3 - boost earns its place |
| Tight mounting space | Primus IQ |
| You want the fault named when something breaks | Prodigy P3 |
Key takeaways
- Both are proportional; neither compromises on braking.
- Memory is the feature that matters most with multiple trailers.
- Boost is specifically useful for heavy loads and long descents.
- A single-trailer owner is not giving anything up with the cheaper unit.
How we sourced this
Every figure on this page came from one of the following, each fetched while the page was written. Where a manufacturer or regulator does not publish a number, we say so rather than estimate it.
Common questions
- Do both need the same harness?
- Both are hardwired controllers and use a vehicle-specific harness. The harness is chosen by vehicle, not by controller.
- Is the P3 harder to set up?
- Slightly - there are more settings available. The core setup is the same gain procedure, done in an empty parking lot at about 25 mph.
- Can either handle a triple-axle trailer?
- Check the published axle rating for the specific model before buying. Axle count is a hard limit on any controller.
More in Trailer Brake Controllers
If the trailer has electric brakes, something has to tell them how hard to work. That something is a controller, and how you set it decides how the rig stops.
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Found something out of date, or a figure you can source better than we did? Corrections get read first. How we research explains how these pages are put together, and contact is one click away.