P2553 code meaning
Throttle/Fuel Inhibit A Circuit Range/Performance
Powertrain system Generic code P25xx codes Check engine light
What P2553 means
P2553 means the throttle/fuel inhibit path A is electrically present but does not behave as commanded. GM's 2005 diagnostic table for the 3.5 L L66 engine files it under electronic throttle control and runs it as a function check of the inhibit relay over a serial data link: a healthy relay produces no serial data, so any data seen there counts as a failure. The test needs battery voltage above 7 V and the key off, and judges a fault within 0.2 s. Like the other inhibit checks in that table it runs once per driving cycle after the ignition is switched off, so the lamp comes on only during the following drive. In that table the throttle valve monitor also has two processors cross-checking each other. P2552 is the general circuit code, P2554 and P2555 voltage faults on the same line.
P2553 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 2.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P2553
- Check engine light on the drive after the fault was found
- Possible reduced power or throttle limp mode
Common causes of P2553
- Most likelyInhibit relay sticking or contacts worn
- PossibleFault in the relay control or feedback wiring
- Less likelyInternal fault in the engine or throttle control unit
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Throttle inhibit aRelay
What each part of P2553 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 5 | Area: vehicle speed, idle control and auxiliary inputs. |
| 53 | The exact fault in that area. |
What to do next
- Note P2553 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2553
What does P2553 mean?
P2553 means "Throttle/Fuel Inhibit A Circuit Range/Performance". P2553 means the throttle/fuel inhibit path A is electrically present but does not behave as commanded. It is a generic code, so it means the same on every make.
Is it safe to drive with P2553?
Drive gently and only to a workshop. With P2553 the car can go into limp mode (reduced power) to protect itself.
Will P2553 fail an emissions test?
Yes, it can. P2553 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2553 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. This is a job for a workshop.
Will P2553 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.