Urgency: Low

Glow Plug Light (Diesel) on a Honda CR-Z

This is usually informational. Address it at your convenience.

What the Glow Plug Light (Diesel) Means on a Honda CR-Z

On a diesel Honda CR-Z, the coiled glow-plug light is normal at start-up: it shows the glow plugs are pre-heating the cylinders. You wait for it to go out before cranking. If it flashes after warm-up, it signals a glow-plug or engine management fault.

How Urgent Is the Glow Plug Light (Diesel)?

Urgency level for this indicator on the Honda CR-Z: low. Reading the colour is the fastest gut-check — a red symbol asks you to stop and investigate quickly, while amber or yellow means schedule a check soon rather than immediately. Green and blue symbols are simply telling you a system is active. Whatever the colour, the safest habit is to note when the Glow Plug Light (Diesel) appeared, how the Honda CR-Z is behaving, and whether the light is steady or flashing, because a flashing warning almost always means act now.

Common Symptoms Alongside the Glow Plug Light (Diesel)

When the Glow Plug Light (Diesel) shows up on a Honda CR-Z, it rarely arrives completely alone — there are usually subtle clues if you know where to look. Drivers often notice a change in how the Honda CR-Z responds, an unfamiliar sound, or a warning message on the instrument cluster. Cataloguing these symptoms is not busywork; each one narrows the list of likely causes and helps a technician zero in on the real fault instead of replacing parts on a hunch.

  • Light on briefly at cold start (normal)
  • Flashing light after warm-up (fault)
  • Hard starting when cold
  • Rough running or white smoke on cold mornings

What Causes the Glow Plug Light (Diesel) to Come On?

There is rarely a single universal reason the Glow Plug Light (Diesel) appears on a Honda CR-Z; instead there is a shortlist of usual suspects. Root causes range from simple, inexpensive items to genuine component failures, which is why a proper diagnosis always beats guessing. Understanding the common triggers on the Honda CR-Z helps you have a more informed conversation with your mechanic and avoid paying for parts you do not need.

  • Normal pre-heat cycle (steady, brief)
  • One or more failed glow plugs
  • Glow plug relay fault
  • Crankshaft/camshaft sensor issue
  • Related engine management fault

How to Fix the Glow Plug Light (Diesel) on a Honda CR-Z

To resolve the Glow Plug Light (Diesel) on your Honda CR-Z, resist the urge to simply disconnect the battery and hope it stays off. A warning that is cleared without addressing the cause almost always returns. The step-by-step approach below is the same logical order a professional follows on the Honda CR-Z: confirm the basics, read the stored codes, then target the actual fault.

  1. At cold start, wait for the light to go out before cranking
  2. If it flashes, scan for glow-plug and engine codes
  3. Test each glow plug for resistance/continuity
  4. Replace failed plugs (ideally as a set) and check the relay
  5. Clear codes and confirm easy cold starts

Is It Safe to Drive With the Glow Plug Light (Diesel) On?

Drivers ask this constantly, and the answer for the Honda CR-Z is nuanced. A steady amber Glow Plug Light (Diesel) with no change in how the car drives usually means you can continue carefully and get it looked at soon. A red or flashing Glow Plug Light (Diesel), unusual noises, warning messages, or a drop in performance are your cue to stop the Honda CR-Z safely and avoid further driving until the cause is known.

Diagnostic Trouble Codes Linked to the Glow Plug Light (Diesel)

If you scan a Honda CR-Z showing this light, these are the OBD-II trouble codes most commonly associated with it. The code you actually retrieve is what pinpoints the repair.

CodeMeaning
P0335 Crankshaft Position Sensor Circuit
The crankshaft position sensor signal is faulty, which can cause stalling or a no-start condition.

Professional Mechanic Tips

Field notes from Marcus Vale, ASE-Certified Master Technician
Hard cold starts plus a flashing glow-plug light on a diesel Honda CR-Z usually means one or more plugs have failed — replace them as a set for even starting.
Do not ignore a flashing glow light; on many diesels it doubles as a general engine fault warning, so scan it rather than guessing.

Frequently Asked Questions

Why is the Glow Plug Light (Diesel) on in my Honda CR-Z?

Your Honda CR-Z turned on the Glow Plug Light (Diesel) after its self-diagnostics flagged an issue in that system. Because several different faults can trigger the same symbol, the smart first move is an OBD-II scan to pull the specific code before you spend any money.

Can I keep driving with the Glow Plug Light (Diesel) on?

It depends on the urgency (low) and how your Honda CR-Z is behaving. If the light is red or flashing, or the car drives differently, stop safely and get help. If it is amber and everything feels normal, you can usually drive to a workshop soon — just do not put off the diagnosis.

How much does it cost to fix the Glow Plug Light (Diesel) on a Honda CR-Z?

There is no single price for the Glow Plug Light (Diesel) on a Honda CR-Z; it ranges from a no-cost adjustment to a component replacement. The honest way to control cost is to diagnose the exact code before authorising any repair, so you only pay to fix what is actually wrong.

Will the Glow Plug Light (Diesel) reset itself on a Honda CR-Z?

Sometimes the Glow Plug Light (Diesel) on a Honda CR-Z clears on its own once the condition that triggered it no longer exists — for example after several good drive cycles. More often, though, the light stays on until the underlying fault is repaired and the code is cleared, so treat a self-clearing light as a reason to still investigate.